Low-dimensional nanostructures such as nanotubes, nanowires, and quantum dots are promising build... more Low-dimensional nanostructures such as nanotubes, nanowires, and quantum dots are promising building blocks for electronic, optical, sensing, and energy conversion applications. For effective device design it is important to understand how the basic thermal properties of nanostructures differ from those of bulk materials. For example, the measured thermal conductivity of silicon nanowires [1] can be understood with a 3-dimensional dispersion relation [2] for diameters down to about 40 nm, although at 22 nm diameter the experiment and modeling diverge sharply.
We report on the magnetic properties of a hot-pressed FeSb2 sample. We find a significant increas... more We report on the magnetic properties of a hot-pressed FeSb2 sample. We find a significant increase in the magnetic susceptibility in our sample when compared with the values previously reported for the polycrystalline sample. The pronounced Curie tail at low temperature corresponds to 0.2% of Fe2+ impurities per mole. In the intrinsic conductivity region, the susceptibility due to free carriers shows thermally activated behavior and is consistent with the data reported for single crystal FeSb2. Based on our data and analysis, while the enhanced magnetic susceptibility in our sample comes mainly from a small amount of unreacted Fe, the contribution from the enhanced carrier density due to lattice and strain defects arising from the ball milling process is also significant. Existence of an unreacted Fe phase is evidenced by small coercivity values of ~100 observed at 50 and 300 K.
An experimental setup for determining the electrical resistivity of several types of thermoelectr... more An experimental setup for determining the electrical resistivity of several types of thermoelectric materials over the temperature range 20 < T < 550 °C is described in detail. One resistivity measurement during temperature cycling is performed and explained for Cu0.01Bi2Te2.7Se0.3 and a second measurement is made on Yb0.35Co4Sb12 as a function of time at 400 °C. Both measurements confirm that the materials are thermally stable for the temperature range and time period measured. Measurements made during temperature cycling show an irreversible decrease in the electrical resistivity of Cu0.01Bi2Te2.7Se0.3 when the measuring temperature exceeds the maximum sample fabrication temperature. Several other possible uses of such a system include but are not limited to studying the effects of annealing and/or oxidation as a function of both temperature and time.
Proceedings of the National Academy of Sciences, 2013
From an environmental perspective, lead-free SnTe would be preferable for solid-state waste heat ... more From an environmental perspective, lead-free SnTe would be preferable for solid-state waste heat recovery if its thermoelectric figure-of-merit could be brought close to that of the lead-containing chalcogenides. In this work, we studied the thermoelectric properties of nanostructured SnTe with different dopants, and found indium-doped SnTe showed extraordinarily large Seebeck coefficients that cannot be explained properly by the conventional two-valence band model. We attributed this enhancement of Seebeck coefficients to resonant levels created by the indium impurities inside the valence band, supported by the first-principles simulations. This, together with the lower thermal conductivity resulting from the decreased grain size by ball milling and hot pressing, improved both the peak and average nondimensional figure-of-merit ( ZT ) significantly. A peak ZT of ∼1.1 was obtained in 0.25 atom % In-doped SnTe at about 873 K.
We present an angle-resolved photoemission spectroscopy study of the electronic structure of SnTe... more We present an angle-resolved photoemission spectroscopy study of the electronic structure of SnTe, and compare the experimental results to ab initio band structure calculations as well as a simplified tight-binding model of the p-bands. Our study reveals the conjectured complex Fermi surface structure near the L-points showing topological changes in the bands from disconnected pockets, to open tubes, and then to cuboids as the binding energy increases, resolving lingering issues about the electronic structure. The chemical potential at the crystal surface is found to be 0.5 eV below the gap, corresponding to a carrier density of p = 1.14 × 10 21 cm −3 or 7.2 × 10 −2 holes per unit cell. At a temperature below the cubic-rhombohedral structural transition a small shift in spectral energy of the valance band is found, in agreement with model predictions.
Elastic neutron-scattering, inelastic x-ray scattering, specific-heat, and pressure-dependent ele... more Elastic neutron-scattering, inelastic x-ray scattering, specific-heat, and pressure-dependent electrical transport measurements have been made on single crystals of AuZn and Au0.52Zn0.48 above and below their martensitic transition temperatures (TM = 64 K and 45 K, respectively). In each composition, elastic neutron scattering detects new commensurate Bragg peaks (modulation) appearing at Q = (1.33, 0.67, 0) at temperatures corresponding to each sample's TM. Although the new Bragg peaks appear in a discontinuous manner in the Au0.52Zn0.48 sample, they appear in a continuous manner in AuZn. Surprising us, the temperature dependence of the AuZn Bragg peak intensity and the specific-heat jump near the transition temperature are in favorable accord with a mean-field approximation. A Landau-theory-based fit to the pressure dependence of the transition temperature suggests the presence of a critical endpoint in the AuZn phase diagram located at T * M = 2.7 K and p * = 3.1 GPa, with a quantum saturation temperature θs = 48.3±3.7 K.
The Seebeck coefficients, electrical resistivities, total thermal conductivities, and magnetizati... more The Seebeck coefficients, electrical resistivities, total thermal conductivities, and magnetization are reported for temperatures between 5 and 350 K for n-type Bi 0.88 Sb 0.12 nano-composite alloys made by Ho-doping at the 0, 1 and 3% atomic levels. The alloys were prepared using a dc hotpressing method, and are shown to be single phase for both Ho contents with grain sizes on the average of 900 nm. We find the parent compound has a maximum of ZT = 0.28 at 231 K, while doping 1% Ho increases the maximum ZT to 0.31 at 221 K and the 3% doped sample suppresses the maximum ZT = 0.24 at a temperature of 260 K.
The specific heat of multiwalled titanium dioxide (anatase phase) nanotubes has been measured bet... more The specific heat of multiwalled titanium dioxide (anatase phase) nanotubes has been measured between 1.5 and 95K. Bulk anatase and rutile were also measured. The nanotube specific heat approaches that of bulk anatase at high temperatures. Below about 50K the nanotube specific heat begins to show large enhancements compared to bulk. Using an isotropic elastic continuum model, this can be understood qualitatively as a transition to low-dimensional behavior. Below about 3K there is a second transition and the nanotube specific heat becomes nearly constant, exceeding bulk anatase by an order of magnitude or more at 1.5K.
In this report, thermal conductivity reduction by more than three orders of magnitude over its si... more In this report, thermal conductivity reduction by more than three orders of magnitude over its single crystal counterpart for the strongly correlated system FeSb2 through a nanostructure approach was presented, leading to a significant increase of thermoelectric figure-of-merit (ZT). For the samples processed with the optimal parameters, the thermal conductivity reached 0.34 Wm−1 K−1 at 50 K, leading to a ZT peak of about 0.013, compared to 0.005 for single crystal FeSb2, an increase of about 160%. This work suggests that nanostructure method is effective and can be possibly extended to other strongly correlated low temperature thermoelectric materials, paving the way for future cryogenic temperature cooling applications.
The evolution of the electronic properties of electron-doped (Sr1−xLax)2IrO4 is experimentally ex... more The evolution of the electronic properties of electron-doped (Sr1−xLax)2IrO4 is experimentally explored as the doping limit of La is approached. As electrons are introduced, the electronic ground state transitions from a spin-orbit Mott phase into an electronically phase separated state, where long-range magnetic order vanishes beyond x = 0.02 and charge transport remains percolative up to the limit of La substitution (x ≈ 0.06). In particular, the electronic ground state remains inhomogeneous even beyond the collapse of the parent state's long-range antiferromagnetic order, while persistent short-range magnetism survives up to the highest La-substitution levels. Furthermore, as electrons are doped into Sr2IrO4, we observe the appearance of a low temperature magnetic glass-like state intermediate to the complete suppression of antiferromagnetic order. Universalities and differences in the electron-doped phase diagrams of single layer and bilayer Ruddlesden-Popper strontium iridates are discussed.
Muon spin spectroscopy has been used to study in detail the onset of large-moment antiferromagnet... more Muon spin spectroscopy has been used to study in detail the onset of large-moment antiferromagnetism (LMAF) in UPt 3 as induced by Th substitution. Zero-field experiments have been carried out on a series of polycrystalline U 1-x Th x Pt 3 (0 ≤ x ≤ 0.05) samples in the temperature range 0.04-10 K. At low Th content (x ≤ 0.002) magnetic ordering on the time scale of the µSR experiment (10-8 s) is not detected. For x = 0.005 a weak magnetic signal appears below T = 2 K, while for 0.006 ≤ x ≤ 0.05, spontaneous oscillations in the µSR spectra signal the presence of the LMAF phase. The data are well described by a two-component depolarization function, combining the contribution of a polycrystalline antiferromagnet and a Kubo-Lorentzian response. However, the transition into the antiferromagnetic phase is quite broad. For x = 0.01 and 0.02, a weak magnetic signal appears below about 7 K, which is well above the mean-field transition temperatures. The broadening may be a result of the effects of disorder on the time fluctuations associated with anomalous small-moment antiferromagnetism.
and his coworkers almost 30 years ago, was recently suggested to possess an unconventional superc... more and his coworkers almost 30 years ago, was recently suggested to possess an unconventional superconducting ground state in the presence of a background of strong spin fluctuations. This signature for this claim stemmed from charge transport and magnetization anomalies near 45K, yet, later a detailed single crystal XRD investigation revealed that the anomaly is produced by a second order superlattice transition and that this transition can be tuned to zero temperature-suggesting a structural quantum critical point. Here in an attempt to characterize this phase further, we present a picture of the evolution of the structural and magnetic behavior in Ca3Ir4(Sn1-xSbx)13 via a combined transport, magnetization and neutron scattering study.
We study the thermoelectric properties of Te-doped FeSb 2 nanostructured samples. Four samples of... more We study the thermoelectric properties of Te-doped FeSb 2 nanostructured samples. Four samples of stoichiometry FeSb 1.84 Te 0.16 were prepared by a hot press method at temperatures of 200, 400, 500, and 600 o C. Te-doping enhances the dimensionless figure of merit (ZT) on FeSb 2 via two mechanisms. First, a semiconductor to metal transition is induced, which enhances the value of the power factor at low-temperatures. Second, the thermal conductivity, which was already reduced in nanostructured FeSb 2 samples, is further reduced by increased point defect scattering through the n type substitution of Sb site by Te atom. The combined effect results in a ZT = 0.022 at 100 K, an increase of 62% over the ZT value for the optimized Te-doped single crystal sample. Hall coefficient and electrical resistivity measurements reveal a decreased mobility and increased concentration of the carriers in the doped sample.
We have studied the thermoelectric properties of nanostructured YbAgCu 4 materials. A high power ... more We have studied the thermoelectric properties of nanostructured YbAgCu 4 materials. A high power factor of ∼131 μW cm −1 K −2 has been obtained at 22 K for nanostructured samples prepared by ball milling the arc melted ingot into nanopowder and hot pressing the nanopowder. The implementation of nanostructuring method decreased the thermal conductivity at 42 K by 30−50% through boundary scattering comparing with the previously reported value of polycrystalline YbAgCu 4. A peak dimensionless thermoelectric figure-of-merit, ZT, of 0.11 has been achieved at 42 K, which may find potential applications for cryogenic cooling below 77 K. The nanostructuring approach can be extended to other heavy Fermion materials to achieve high power factor and low thermal conductivity and ultimately higher ZT.
The thermoelectric properties of Bi-FeSb2 nanocomposites are reported. The electrical resistivity... more The thermoelectric properties of Bi-FeSb2 nanocomposites are reported. The electrical resistivity and the Seebeck coefficient measurements show a significant dependence on bismuth concentration. Our results reveal that the shifting of the Seebeck peak in FeSb2 nanocomposites is purely a grain size-effect. The thermal conductivity data indicates a presence of an electron-phonon interaction. Over all, our analysis of the the thermoelectric properties of Bi-FeSb2 nanocomposites provide additional evidence for phonon-drag in FeSb2.
Department of Physics, Boston College, Chestnut Hill, Massachusetts 02467. Los Alamos National La... more Department of Physics, Boston College, Chestnut Hill, Massachusetts 02467. Los Alamos National Laboratory, Los Alamos, New Mexico 87545. CeCoIn5 is an unconventional, d-wave, heavy fermion superconductor with a critical temperature of ˜2.3K. The physical properties of doped samples of CeCo1-xMxIn5, where M is Fe, Cr, Rh, Ru, Ir, Mn, Ni, V, or Cu for x <=0.03, are characterized. Resistivity, magnetoresistance, and magnetization are measured in a temperature range 5 - 300K and magnetic field up to 9 Tesla; the magnetization is measured using a capacitive cantilever magnetometer. The effect of the dopants on resistivity and magnetization, with regard to percentage x present in the sample, provides valuable insight into the character of the parent material CeCoIn5. Implications of magnetic, diamagnetic, and non-magnetic doping of CeCoIn5 will be discussed.
Low-dimensional nanostructures such as nanotubes, nanowires, and quantum dots are promising build... more Low-dimensional nanostructures such as nanotubes, nanowires, and quantum dots are promising building blocks for electronic, optical, sensing, and energy conversion applications. For effective device design it is important to understand how the basic thermal properties of nanostructures differ from those of bulk materials. For example, the measured thermal conductivity of silicon nanowires [1] can be understood with a 3-dimensional dispersion relation [2] for diameters down to about 40 nm, although at 22 nm diameter the experiment and modeling diverge sharply.
We report on the magnetic properties of a hot-pressed FeSb2 sample. We find a significant increas... more We report on the magnetic properties of a hot-pressed FeSb2 sample. We find a significant increase in the magnetic susceptibility in our sample when compared with the values previously reported for the polycrystalline sample. The pronounced Curie tail at low temperature corresponds to 0.2% of Fe2+ impurities per mole. In the intrinsic conductivity region, the susceptibility due to free carriers shows thermally activated behavior and is consistent with the data reported for single crystal FeSb2. Based on our data and analysis, while the enhanced magnetic susceptibility in our sample comes mainly from a small amount of unreacted Fe, the contribution from the enhanced carrier density due to lattice and strain defects arising from the ball milling process is also significant. Existence of an unreacted Fe phase is evidenced by small coercivity values of ~100 observed at 50 and 300 K.
An experimental setup for determining the electrical resistivity of several types of thermoelectr... more An experimental setup for determining the electrical resistivity of several types of thermoelectric materials over the temperature range 20 < T < 550 °C is described in detail. One resistivity measurement during temperature cycling is performed and explained for Cu0.01Bi2Te2.7Se0.3 and a second measurement is made on Yb0.35Co4Sb12 as a function of time at 400 °C. Both measurements confirm that the materials are thermally stable for the temperature range and time period measured. Measurements made during temperature cycling show an irreversible decrease in the electrical resistivity of Cu0.01Bi2Te2.7Se0.3 when the measuring temperature exceeds the maximum sample fabrication temperature. Several other possible uses of such a system include but are not limited to studying the effects of annealing and/or oxidation as a function of both temperature and time.
Proceedings of the National Academy of Sciences, 2013
From an environmental perspective, lead-free SnTe would be preferable for solid-state waste heat ... more From an environmental perspective, lead-free SnTe would be preferable for solid-state waste heat recovery if its thermoelectric figure-of-merit could be brought close to that of the lead-containing chalcogenides. In this work, we studied the thermoelectric properties of nanostructured SnTe with different dopants, and found indium-doped SnTe showed extraordinarily large Seebeck coefficients that cannot be explained properly by the conventional two-valence band model. We attributed this enhancement of Seebeck coefficients to resonant levels created by the indium impurities inside the valence band, supported by the first-principles simulations. This, together with the lower thermal conductivity resulting from the decreased grain size by ball milling and hot pressing, improved both the peak and average nondimensional figure-of-merit ( ZT ) significantly. A peak ZT of ∼1.1 was obtained in 0.25 atom % In-doped SnTe at about 873 K.
We present an angle-resolved photoemission spectroscopy study of the electronic structure of SnTe... more We present an angle-resolved photoemission spectroscopy study of the electronic structure of SnTe, and compare the experimental results to ab initio band structure calculations as well as a simplified tight-binding model of the p-bands. Our study reveals the conjectured complex Fermi surface structure near the L-points showing topological changes in the bands from disconnected pockets, to open tubes, and then to cuboids as the binding energy increases, resolving lingering issues about the electronic structure. The chemical potential at the crystal surface is found to be 0.5 eV below the gap, corresponding to a carrier density of p = 1.14 × 10 21 cm −3 or 7.2 × 10 −2 holes per unit cell. At a temperature below the cubic-rhombohedral structural transition a small shift in spectral energy of the valance band is found, in agreement with model predictions.
Elastic neutron-scattering, inelastic x-ray scattering, specific-heat, and pressure-dependent ele... more Elastic neutron-scattering, inelastic x-ray scattering, specific-heat, and pressure-dependent electrical transport measurements have been made on single crystals of AuZn and Au0.52Zn0.48 above and below their martensitic transition temperatures (TM = 64 K and 45 K, respectively). In each composition, elastic neutron scattering detects new commensurate Bragg peaks (modulation) appearing at Q = (1.33, 0.67, 0) at temperatures corresponding to each sample's TM. Although the new Bragg peaks appear in a discontinuous manner in the Au0.52Zn0.48 sample, they appear in a continuous manner in AuZn. Surprising us, the temperature dependence of the AuZn Bragg peak intensity and the specific-heat jump near the transition temperature are in favorable accord with a mean-field approximation. A Landau-theory-based fit to the pressure dependence of the transition temperature suggests the presence of a critical endpoint in the AuZn phase diagram located at T * M = 2.7 K and p * = 3.1 GPa, with a quantum saturation temperature θs = 48.3±3.7 K.
The Seebeck coefficients, electrical resistivities, total thermal conductivities, and magnetizati... more The Seebeck coefficients, electrical resistivities, total thermal conductivities, and magnetization are reported for temperatures between 5 and 350 K for n-type Bi 0.88 Sb 0.12 nano-composite alloys made by Ho-doping at the 0, 1 and 3% atomic levels. The alloys were prepared using a dc hotpressing method, and are shown to be single phase for both Ho contents with grain sizes on the average of 900 nm. We find the parent compound has a maximum of ZT = 0.28 at 231 K, while doping 1% Ho increases the maximum ZT to 0.31 at 221 K and the 3% doped sample suppresses the maximum ZT = 0.24 at a temperature of 260 K.
The specific heat of multiwalled titanium dioxide (anatase phase) nanotubes has been measured bet... more The specific heat of multiwalled titanium dioxide (anatase phase) nanotubes has been measured between 1.5 and 95K. Bulk anatase and rutile were also measured. The nanotube specific heat approaches that of bulk anatase at high temperatures. Below about 50K the nanotube specific heat begins to show large enhancements compared to bulk. Using an isotropic elastic continuum model, this can be understood qualitatively as a transition to low-dimensional behavior. Below about 3K there is a second transition and the nanotube specific heat becomes nearly constant, exceeding bulk anatase by an order of magnitude or more at 1.5K.
In this report, thermal conductivity reduction by more than three orders of magnitude over its si... more In this report, thermal conductivity reduction by more than three orders of magnitude over its single crystal counterpart for the strongly correlated system FeSb2 through a nanostructure approach was presented, leading to a significant increase of thermoelectric figure-of-merit (ZT). For the samples processed with the optimal parameters, the thermal conductivity reached 0.34 Wm−1 K−1 at 50 K, leading to a ZT peak of about 0.013, compared to 0.005 for single crystal FeSb2, an increase of about 160%. This work suggests that nanostructure method is effective and can be possibly extended to other strongly correlated low temperature thermoelectric materials, paving the way for future cryogenic temperature cooling applications.
The evolution of the electronic properties of electron-doped (Sr1−xLax)2IrO4 is experimentally ex... more The evolution of the electronic properties of electron-doped (Sr1−xLax)2IrO4 is experimentally explored as the doping limit of La is approached. As electrons are introduced, the electronic ground state transitions from a spin-orbit Mott phase into an electronically phase separated state, where long-range magnetic order vanishes beyond x = 0.02 and charge transport remains percolative up to the limit of La substitution (x ≈ 0.06). In particular, the electronic ground state remains inhomogeneous even beyond the collapse of the parent state's long-range antiferromagnetic order, while persistent short-range magnetism survives up to the highest La-substitution levels. Furthermore, as electrons are doped into Sr2IrO4, we observe the appearance of a low temperature magnetic glass-like state intermediate to the complete suppression of antiferromagnetic order. Universalities and differences in the electron-doped phase diagrams of single layer and bilayer Ruddlesden-Popper strontium iridates are discussed.
Muon spin spectroscopy has been used to study in detail the onset of large-moment antiferromagnet... more Muon spin spectroscopy has been used to study in detail the onset of large-moment antiferromagnetism (LMAF) in UPt 3 as induced by Th substitution. Zero-field experiments have been carried out on a series of polycrystalline U 1-x Th x Pt 3 (0 ≤ x ≤ 0.05) samples in the temperature range 0.04-10 K. At low Th content (x ≤ 0.002) magnetic ordering on the time scale of the µSR experiment (10-8 s) is not detected. For x = 0.005 a weak magnetic signal appears below T = 2 K, while for 0.006 ≤ x ≤ 0.05, spontaneous oscillations in the µSR spectra signal the presence of the LMAF phase. The data are well described by a two-component depolarization function, combining the contribution of a polycrystalline antiferromagnet and a Kubo-Lorentzian response. However, the transition into the antiferromagnetic phase is quite broad. For x = 0.01 and 0.02, a weak magnetic signal appears below about 7 K, which is well above the mean-field transition temperatures. The broadening may be a result of the effects of disorder on the time fluctuations associated with anomalous small-moment antiferromagnetism.
and his coworkers almost 30 years ago, was recently suggested to possess an unconventional superc... more and his coworkers almost 30 years ago, was recently suggested to possess an unconventional superconducting ground state in the presence of a background of strong spin fluctuations. This signature for this claim stemmed from charge transport and magnetization anomalies near 45K, yet, later a detailed single crystal XRD investigation revealed that the anomaly is produced by a second order superlattice transition and that this transition can be tuned to zero temperature-suggesting a structural quantum critical point. Here in an attempt to characterize this phase further, we present a picture of the evolution of the structural and magnetic behavior in Ca3Ir4(Sn1-xSbx)13 via a combined transport, magnetization and neutron scattering study.
We study the thermoelectric properties of Te-doped FeSb 2 nanostructured samples. Four samples of... more We study the thermoelectric properties of Te-doped FeSb 2 nanostructured samples. Four samples of stoichiometry FeSb 1.84 Te 0.16 were prepared by a hot press method at temperatures of 200, 400, 500, and 600 o C. Te-doping enhances the dimensionless figure of merit (ZT) on FeSb 2 via two mechanisms. First, a semiconductor to metal transition is induced, which enhances the value of the power factor at low-temperatures. Second, the thermal conductivity, which was already reduced in nanostructured FeSb 2 samples, is further reduced by increased point defect scattering through the n type substitution of Sb site by Te atom. The combined effect results in a ZT = 0.022 at 100 K, an increase of 62% over the ZT value for the optimized Te-doped single crystal sample. Hall coefficient and electrical resistivity measurements reveal a decreased mobility and increased concentration of the carriers in the doped sample.
We have studied the thermoelectric properties of nanostructured YbAgCu 4 materials. A high power ... more We have studied the thermoelectric properties of nanostructured YbAgCu 4 materials. A high power factor of ∼131 μW cm −1 K −2 has been obtained at 22 K for nanostructured samples prepared by ball milling the arc melted ingot into nanopowder and hot pressing the nanopowder. The implementation of nanostructuring method decreased the thermal conductivity at 42 K by 30−50% through boundary scattering comparing with the previously reported value of polycrystalline YbAgCu 4. A peak dimensionless thermoelectric figure-of-merit, ZT, of 0.11 has been achieved at 42 K, which may find potential applications for cryogenic cooling below 77 K. The nanostructuring approach can be extended to other heavy Fermion materials to achieve high power factor and low thermal conductivity and ultimately higher ZT.
The thermoelectric properties of Bi-FeSb2 nanocomposites are reported. The electrical resistivity... more The thermoelectric properties of Bi-FeSb2 nanocomposites are reported. The electrical resistivity and the Seebeck coefficient measurements show a significant dependence on bismuth concentration. Our results reveal that the shifting of the Seebeck peak in FeSb2 nanocomposites is purely a grain size-effect. The thermal conductivity data indicates a presence of an electron-phonon interaction. Over all, our analysis of the the thermoelectric properties of Bi-FeSb2 nanocomposites provide additional evidence for phonon-drag in FeSb2.
Department of Physics, Boston College, Chestnut Hill, Massachusetts 02467. Los Alamos National La... more Department of Physics, Boston College, Chestnut Hill, Massachusetts 02467. Los Alamos National Laboratory, Los Alamos, New Mexico 87545. CeCoIn5 is an unconventional, d-wave, heavy fermion superconductor with a critical temperature of ˜2.3K. The physical properties of doped samples of CeCo1-xMxIn5, where M is Fe, Cr, Rh, Ru, Ir, Mn, Ni, V, or Cu for x <=0.03, are characterized. Resistivity, magnetoresistance, and magnetization are measured in a temperature range 5 - 300K and magnetic field up to 9 Tesla; the magnetization is measured using a capacitive cantilever magnetometer. The effect of the dopants on resistivity and magnetization, with regard to percentage x present in the sample, provides valuable insight into the character of the parent material CeCoIn5. Implications of magnetic, diamagnetic, and non-magnetic doping of CeCoIn5 will be discussed.
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