N. Ong - Academia.edu (original) (raw)

Papers by N. Ong

Research paper thumbnail of Electrical and magnetic properties of a series of ternary barium metal ruthenates: Ba 3 M Ru 2 O 9 ( M = Fe , Co, Ni, Cu, and In)

Physical Review B, 1998

ABSTRACT The resistivities and magnetic susceptibilities of the Ba3MRu2O9 series of compounds, wi... more ABSTRACT The resistivities and magnetic susceptibilities of the Ba3MRu2O9 series of compounds, with M=Fe, Co, Ni, Cu, and In, are reported. All compounds have regular or distorted versions of the hexagonal barium titanate structure, consisting of chains of face-sharing RuO6 octahedra interconnected by corner-sharing MO6 octahedra. The compounds are semiconductors with ρ>0.1 Ω cm at ambient temperature. The magnetic susceptibilities below 400 K show that the 3d elements display local moments, and that the variants with M=Co, Ni, and Cu have magnetic transitions near 100 K.

Research paper thumbnail of Orientational anisotropy of the upper critical field in single-crystal YBa2Cu3O7 and Bi2.2CaSr1.9Cu2O8+x

Physical review. B, Condensed matter, 1988

... University of Pennsylvania, Philadelphia, Pennsylvania 19104 RV Chamberlin Department of Phys... more ... University of Pennsylvania, Philadelphia, Pennsylvania 19104 RV Chamberlin Department of Physics, Arizona State University, Tempe, Arizona 85287 ZZ Wang, TW ... characterized by x-ray and other spectroscopies.8 The resistive transition (0.5 mA at 28 Hz) in zero field was at ...

Research paper thumbnail of Variation of superconductivity with carrier concentration in oxygen-doped YBa2Cu3O7-y

Physical review. B, Condensed matter, 1987

The Hall coefficient R H , the volume fraction f showing the Meissner effect, and the superconduc... more The Hall coefficient R H , the volume fraction f showing the Meissner effect, and the superconducting transition temperature T c have been measured in the high-T c oxide YBa 2 Cu 3 O 7-y for a range of oxygen vacancy concentration 0.0<y<0.7. We find that R H , f, and T c are insensitive to ...

Research paper thumbnail of Unusual 1/T3 temperature dependence of the Hall conductivity in YBa2Cu3O7-δ

Physical Review B, 1991

ABSTRACT Measurements of the Hall coefficient RH and resistivity ρa of YBa2Cu3O7 disclose anomali... more ABSTRACT Measurements of the Hall coefficient RH and resistivity ρa of YBa2Cu3O7 disclose anomalies in their temperature (T) dependences. The 1/RH vs T curve has a negative curvature, while dρa/dT displays a previously unreported step near 290 K. The Hall conductivity σH follows an unusual 1/T3 dependence from 100 to 360 K. We contrast the results with predictions of conventional Bloch theory, and compare them with recent calculations based on large-U models. Implications for cyclotron damping at low T are discussed.

Research paper thumbnail of Transport and magnetic properties of BaMo6S8: Some evidence for charge-density waves

Physica B+C, 1985

... FISCHER D partement de la Mati re Condens e, Universit de Gen ve, 24 Quai Ernest-Ansermet, 12... more ... FISCHER D partement de la Mati re Condens e, Universit de Gen ve, 24 Quai Ernest-Ansermet, 1211 Gen ve-4, Switzerland XJ ZHANG* and NP ONG Department of Physics, University of Southern California, Los Angeles, CA 90089-0484, USA The compounds MMo6S8 (M ...

Research paper thumbnail of Sample length and frequency dependence of the voltage-oscillation amplitude in NbSe_{3}

Research paper thumbnail of Optical anisotropy of YBa_{2}Cu_{3}O_{7-x}

Physical Review B, 1988

The optical anisotropy of YBa2Cu3O7-x in the 0.08-5.6 eV region is investigated by polarized refl... more The optical anisotropy of YBa2Cu3O7-x in the 0.08-5.6 eV region is investigated by polarized reflectance measurements on single crystals, and by transmittance, reflectance, and ellipsometric measurements on oriented thin films. In the visible-near-uv spectral region the anisotropy is relatively mild, but a huge anisotropy is observed in the infrared. Here, the reflectance increases with decreasing frequency for both polraizations, consistent

Research paper thumbnail of Infrared reflectivity of single-crystal Bi2Mm+1ComOy (M=Ca,Sr,Ba; m=1,2), Bi2Sr3Fe2O9.2, and Bi2Sr2MnO6.25, isomorphic to Bi-Cu-based high-Tc oxides

Physical Review B, 1991

Infrared reflectivity of single-crystal BizM + tCo Oy (M =Ca,Sr,Ba; m = 1,2), Bi2Sr3Fe2O9 2, and ... more Infrared reflectivity of single-crystal BizM + tCo Oy (M =Ca,Sr,Ba; m = 1,2), Bi2Sr3Fe2O9 2, and BizSr2Mn06 z5, isomorphic to Bi-Cu-based high-T, oxides

Research paper thumbnail of Hall effect of the high-T_{c} superconducting oxides Bi-Ca-Sr-Cu-O and Tl_{2}Ca_{2}Ba_{2}Cu_{3}O_{x}

Physical Review B, 1988

ABSTRACT

Research paper thumbnail of Approaching the Mott-Hubbard insulator in the 85-K superconductor Bi2(Sr,Ca)3Cu2O8+d by doping with Tm

Physical Review B, 1989

As x increases in Bi4Sr3Ca3-xTmxCu4O16+y the Hall carrier density nH decreases linearly. The vari... more As x increases in Bi4Sr3Ca3-xTmxCu4O16+y the Hall carrier density nH decreases linearly. The variation is consistent with Mott-Hubbard behavior, but in conflict with band-structure results which ignore correlations. We find that the variation of Tc vs nH is nonmonotonic. The source of the large carrier population (0.4/Cu) in the undoped (x=0) compound is discussed.

Research paper thumbnail of Quantized voltage jumps observed in the charge-density-wave conduction noise in TaS_{3}

Physical Review B, 1984

ABSTRACT

Research paper thumbnail of Hall-effect measurements of HgBa2CaCu2O6+δ

Physical Review B, 1994

The resistivity [rho] and Hall coefficient [ital R][sub [ital H]] have been measured for samples ... more The resistivity [rho] and Hall coefficient [ital R][sub [ital H]] have been measured for samples of the two-plane superconductor HgBa[sub 2]CaCu[sub 2]O[sub 6+[delta]] ([ital T][sub [ital c]][similar to]124 K) with different annealing histories. The observed temperature dependence [ital R][sub [ital H]][similar to]1/[ital T] (up to 470 K) matches the steep dependence previously seen in 90-K YBa[sub 2]Cu[sub 3]O[sub 7[minus][delta]] and

Research paper thumbnail of Diverging resistivity anisotropy with decreasing temperature in 60-K YBa2Cu2O7-y

Physical Review B, 1989

ABSTRACT The in-plane resistivity ρ{sub {ital ab}} of 60-K YBaâCuâO{sub 7-{ital y}} is equal to ... more ABSTRACT The in-plane resistivity ρ{sub {ital ab}} of 60-K YBaâCuâO{sub 7-{ital y}} is equal to (340{plus minus}30) μΩ cm at 290 K and varies approximately linearly with temperature {ital T}. The anisotropy ρ{sub {ital c}}/ρ{sub ab} increases from {similar to}100 to 2000 as {ital T} decreases from 290 to 80 K. In the four crystals studied ρ{sub {ital c}} is observed to increase monotonically with decreasing {ital T}. This is an intrinsic property of the normal state which has not been explained by conventional transport theory.

Research paper thumbnail of Growth, structural, and physical properties of superconducting Nd2-xCexCuO4 crystals

Physical Review B, 1989

Single crystals of the n-type Nd-Ce-Cu-0 superconducting materials have been grown via a Aux tech... more Single crystals of the n-type Nd-Ce-Cu-0 superconducting materials have been grown via a Aux technique, and their structural and physical properties characterized. Optimum crystal growth conditions were arrived at from a survey of various compositions and temperatures. We determine that the charge composition (50 mol% Nd203-Ce02, 50 mol%%uo CuO) held at a temperature of 1300'C and followed by a slow cooling to 1000'C produces plateletlike crystals of the n-type phase Nd~Ce Cu04, which, after being annealed at 900'C in nitrogen, become superconducting. The limit of the Ce solubility is x =0. 18, and only crystals having a Ce content between 0.14 and 0.17 were found to superconductors, with the rnaximurn I', occurring at x =0.14. The oxygen uptake and loss in the Nd material is similar to that measured on La2Cu04 but occurs at higher temperatures (750'C instead of 500 C). The large Meissner fraction indicates bulk superconductivity. However, due to a complex microstructure or compositional (e.g. , oxygen) inhomogeneities in the crystal, zero resistance is dificult to achieve. The resistivity temperature dependence above T, is metalliclike, and linear above 150 K, in contrast to bulk ceramics. Finally, no evidence for rnagnetic ordering over the temperature range 4-350 K was observed for the superconducting Ce-doped Nd&CuO4 phase, whereas signs of magnetic ordering were found at 340 K for the undoped material. pounds (e.g. , insulating LazCuO4 doped with Sr leads to a 40 K superconducting La2 Sr CuO&, Refs. 6-8). The formation of Cu with a valence greater than 2 (i.e. , oxidation of Cu) implies the introduction of a hole charge state. These holes, or missing electrons, are the charge carriers in all these cuprate superconductors and they are called, for this reason, p type. Recently Tokura et al. discovered a new class of materials Nd2 Ce Cu04 which are n-type superconductors at 23 K. They did this by chemically reducing the Cu (i.e. , doping the system with electrons) in two steps: (1) the replacement of trivalent (Nd) by tetravalent ions (Ce), and (2) the removal of oxygen. This new superconducting phase still contains CuOz planes, but the carriers are electrons (n type) and not holes (p type). The n-type charcharacter has been determined by Hall and Seebeck measurements , ' and x-ray absorption measurements" on polycrystalline samples indicate the presence of Cu+ scaling with Ce. Additional evidence supporting n-type conductivity in these new electron-doped superconductors is that the replacement of oxygen by fluorine (i.e. , again a reduction of the Cu) also induces superconductivity. ' By replacing the Nd in the parent compound Nd2, Ce"Cu04by other rare earths (Pr, Sm, Eu), and the Ce by Th, additional new n-type superconducting phases have been synthesized. ' '

Research paper thumbnail of Anomalous hysteresis in the Josephson plasma resonance of Bi2Sr2CaCuO8+δ for fields close to alignment with the ab plane

Research paper thumbnail of Out-of-plane conductivity in single-crystal YBa_{2}Cu_{3}O_{7}

Physical Review B, 1988

The resistivity anisotropy has been measured in seven single crystals of YBa2Cu307. %e 6nd that t... more The resistivity anisotropy has been measured in seven single crystals of YBa2Cu307. %e 6nd that the anisotropy is between 56 and 110 at 290 K, increasing to -250 just above T, (90-93 K). While the out-of-plane resistivity p, is close to the Mott limit, the large in-plane ...

Research paper thumbnail of Anomalous in-plane paraconductivity in single-crystal YBa_{2}Cu_{3}O_{7}

Physical Review B, 1988

We have studied the in-plane paraconductivity in single crystals of YBa2Cu3O7 with exceptionally ... more We have studied the in-plane paraconductivity in single crystals of YBa2Cu3O7 with exceptionally sharp transitions. For temperatures greater than ~1 K above the transition temperature Tc, we find good qualitative and some quantitative agreement with the two-dimmensional Aslamazov-Larkin theory. The jump to zero resistance occurs in a narrow interval of less than 0.5 K. Our data are inconsistent with the Lawrence-Doniach expression for crossover from two to three dimensions.

Research paper thumbnail of Mid-infrared reflectivity and ellipsometry measurements on single-crystal YBa2Cu3O7 and Bi2Sr2CuO6+y

Research paper thumbnail of Phase-plot studies of the alternating charge-density-wave current in niobium triselenide

Physical Review B, 1985

Phase plots of ICDW (the charge-density-wave current) versus the applied electric field E are pre... more Phase plots of ICDW (the charge-density-wave current) versus the applied electric field E are presented for driving frequencies 300 kHz to 3 MHz in NbSe3. When E exceeds the threshold value, inductive behavior (I lags E) appears. The strong hysteresis observed is inconsistent with the single-oscillator model. We compare the results with predictions of the overdamped pendulum equation and the transient overshoot phenomenon.

Research paper thumbnail of Nonlinear ac dynamics of charge-density-wave condensate in NbSe_{3}

Physical Review B, 1983

Phase-space plots of the ac charge-density-wave (CDW) current versus the ac voltage have been obt... more Phase-space plots of the ac charge-density-wave (CDW) current versus the ac voltage have been obtained in NbSe3 for frequencies 0.1-5 MHz. The strong inductive hysteresis observed is consistent with metastable states in the CDW and incompatible with classical oscillator models.

Research paper thumbnail of Electrical and magnetic properties of a series of ternary barium metal ruthenates: Ba 3 M Ru 2 O 9 ( M = Fe , Co, Ni, Cu, and In)

Physical Review B, 1998

ABSTRACT The resistivities and magnetic susceptibilities of the Ba3MRu2O9 series of compounds, wi... more ABSTRACT The resistivities and magnetic susceptibilities of the Ba3MRu2O9 series of compounds, with M=Fe, Co, Ni, Cu, and In, are reported. All compounds have regular or distorted versions of the hexagonal barium titanate structure, consisting of chains of face-sharing RuO6 octahedra interconnected by corner-sharing MO6 octahedra. The compounds are semiconductors with ρ>0.1 Ω cm at ambient temperature. The magnetic susceptibilities below 400 K show that the 3d elements display local moments, and that the variants with M=Co, Ni, and Cu have magnetic transitions near 100 K.

Research paper thumbnail of Orientational anisotropy of the upper critical field in single-crystal YBa2Cu3O7 and Bi2.2CaSr1.9Cu2O8+x

Physical review. B, Condensed matter, 1988

... University of Pennsylvania, Philadelphia, Pennsylvania 19104 RV Chamberlin Department of Phys... more ... University of Pennsylvania, Philadelphia, Pennsylvania 19104 RV Chamberlin Department of Physics, Arizona State University, Tempe, Arizona 85287 ZZ Wang, TW ... characterized by x-ray and other spectroscopies.8 The resistive transition (0.5 mA at 28 Hz) in zero field was at ...

Research paper thumbnail of Variation of superconductivity with carrier concentration in oxygen-doped YBa2Cu3O7-y

Physical review. B, Condensed matter, 1987

The Hall coefficient R H , the volume fraction f showing the Meissner effect, and the superconduc... more The Hall coefficient R H , the volume fraction f showing the Meissner effect, and the superconducting transition temperature T c have been measured in the high-T c oxide YBa 2 Cu 3 O 7-y for a range of oxygen vacancy concentration 0.0<y<0.7. We find that R H , f, and T c are insensitive to ...

Research paper thumbnail of Unusual 1/T3 temperature dependence of the Hall conductivity in YBa2Cu3O7-δ

Physical Review B, 1991

ABSTRACT Measurements of the Hall coefficient RH and resistivity ρa of YBa2Cu3O7 disclose anomali... more ABSTRACT Measurements of the Hall coefficient RH and resistivity ρa of YBa2Cu3O7 disclose anomalies in their temperature (T) dependences. The 1/RH vs T curve has a negative curvature, while dρa/dT displays a previously unreported step near 290 K. The Hall conductivity σH follows an unusual 1/T3 dependence from 100 to 360 K. We contrast the results with predictions of conventional Bloch theory, and compare them with recent calculations based on large-U models. Implications for cyclotron damping at low T are discussed.

Research paper thumbnail of Transport and magnetic properties of BaMo6S8: Some evidence for charge-density waves

Physica B+C, 1985

... FISCHER D partement de la Mati re Condens e, Universit de Gen ve, 24 Quai Ernest-Ansermet, 12... more ... FISCHER D partement de la Mati re Condens e, Universit de Gen ve, 24 Quai Ernest-Ansermet, 1211 Gen ve-4, Switzerland XJ ZHANG* and NP ONG Department of Physics, University of Southern California, Los Angeles, CA 90089-0484, USA The compounds MMo6S8 (M ...

Research paper thumbnail of Sample length and frequency dependence of the voltage-oscillation amplitude in NbSe_{3}

Research paper thumbnail of Optical anisotropy of YBa_{2}Cu_{3}O_{7-x}

Physical Review B, 1988

The optical anisotropy of YBa2Cu3O7-x in the 0.08-5.6 eV region is investigated by polarized refl... more The optical anisotropy of YBa2Cu3O7-x in the 0.08-5.6 eV region is investigated by polarized reflectance measurements on single crystals, and by transmittance, reflectance, and ellipsometric measurements on oriented thin films. In the visible-near-uv spectral region the anisotropy is relatively mild, but a huge anisotropy is observed in the infrared. Here, the reflectance increases with decreasing frequency for both polraizations, consistent

Research paper thumbnail of Infrared reflectivity of single-crystal Bi2Mm+1ComOy (M=Ca,Sr,Ba; m=1,2), Bi2Sr3Fe2O9.2, and Bi2Sr2MnO6.25, isomorphic to Bi-Cu-based high-Tc oxides

Physical Review B, 1991

Infrared reflectivity of single-crystal BizM + tCo Oy (M =Ca,Sr,Ba; m = 1,2), Bi2Sr3Fe2O9 2, and ... more Infrared reflectivity of single-crystal BizM + tCo Oy (M =Ca,Sr,Ba; m = 1,2), Bi2Sr3Fe2O9 2, and BizSr2Mn06 z5, isomorphic to Bi-Cu-based high-T, oxides

Research paper thumbnail of Hall effect of the high-T_{c} superconducting oxides Bi-Ca-Sr-Cu-O and Tl_{2}Ca_{2}Ba_{2}Cu_{3}O_{x}

Physical Review B, 1988

ABSTRACT

Research paper thumbnail of Approaching the Mott-Hubbard insulator in the 85-K superconductor Bi2(Sr,Ca)3Cu2O8+d by doping with Tm

Physical Review B, 1989

As x increases in Bi4Sr3Ca3-xTmxCu4O16+y the Hall carrier density nH decreases linearly. The vari... more As x increases in Bi4Sr3Ca3-xTmxCu4O16+y the Hall carrier density nH decreases linearly. The variation is consistent with Mott-Hubbard behavior, but in conflict with band-structure results which ignore correlations. We find that the variation of Tc vs nH is nonmonotonic. The source of the large carrier population (0.4/Cu) in the undoped (x=0) compound is discussed.

Research paper thumbnail of Quantized voltage jumps observed in the charge-density-wave conduction noise in TaS_{3}

Physical Review B, 1984

ABSTRACT

Research paper thumbnail of Hall-effect measurements of HgBa2CaCu2O6+δ

Physical Review B, 1994

The resistivity [rho] and Hall coefficient [ital R][sub [ital H]] have been measured for samples ... more The resistivity [rho] and Hall coefficient [ital R][sub [ital H]] have been measured for samples of the two-plane superconductor HgBa[sub 2]CaCu[sub 2]O[sub 6+[delta]] ([ital T][sub [ital c]][similar to]124 K) with different annealing histories. The observed temperature dependence [ital R][sub [ital H]][similar to]1/[ital T] (up to 470 K) matches the steep dependence previously seen in 90-K YBa[sub 2]Cu[sub 3]O[sub 7[minus][delta]] and

Research paper thumbnail of Diverging resistivity anisotropy with decreasing temperature in 60-K YBa2Cu2O7-y

Physical Review B, 1989

ABSTRACT The in-plane resistivity ρ{sub {ital ab}} of 60-K YBaâCuâO{sub 7-{ital y}} is equal to ... more ABSTRACT The in-plane resistivity ρ{sub {ital ab}} of 60-K YBaâCuâO{sub 7-{ital y}} is equal to (340{plus minus}30) μΩ cm at 290 K and varies approximately linearly with temperature {ital T}. The anisotropy ρ{sub {ital c}}/ρ{sub ab} increases from {similar to}100 to 2000 as {ital T} decreases from 290 to 80 K. In the four crystals studied ρ{sub {ital c}} is observed to increase monotonically with decreasing {ital T}. This is an intrinsic property of the normal state which has not been explained by conventional transport theory.

Research paper thumbnail of Growth, structural, and physical properties of superconducting Nd2-xCexCuO4 crystals

Physical Review B, 1989

Single crystals of the n-type Nd-Ce-Cu-0 superconducting materials have been grown via a Aux tech... more Single crystals of the n-type Nd-Ce-Cu-0 superconducting materials have been grown via a Aux technique, and their structural and physical properties characterized. Optimum crystal growth conditions were arrived at from a survey of various compositions and temperatures. We determine that the charge composition (50 mol% Nd203-Ce02, 50 mol%%uo CuO) held at a temperature of 1300'C and followed by a slow cooling to 1000'C produces plateletlike crystals of the n-type phase Nd~Ce Cu04, which, after being annealed at 900'C in nitrogen, become superconducting. The limit of the Ce solubility is x =0. 18, and only crystals having a Ce content between 0.14 and 0.17 were found to superconductors, with the rnaximurn I', occurring at x =0.14. The oxygen uptake and loss in the Nd material is similar to that measured on La2Cu04 but occurs at higher temperatures (750'C instead of 500 C). The large Meissner fraction indicates bulk superconductivity. However, due to a complex microstructure or compositional (e.g. , oxygen) inhomogeneities in the crystal, zero resistance is dificult to achieve. The resistivity temperature dependence above T, is metalliclike, and linear above 150 K, in contrast to bulk ceramics. Finally, no evidence for rnagnetic ordering over the temperature range 4-350 K was observed for the superconducting Ce-doped Nd&CuO4 phase, whereas signs of magnetic ordering were found at 340 K for the undoped material. pounds (e.g. , insulating LazCuO4 doped with Sr leads to a 40 K superconducting La2 Sr CuO&, Refs. 6-8). The formation of Cu with a valence greater than 2 (i.e. , oxidation of Cu) implies the introduction of a hole charge state. These holes, or missing electrons, are the charge carriers in all these cuprate superconductors and they are called, for this reason, p type. Recently Tokura et al. discovered a new class of materials Nd2 Ce Cu04 which are n-type superconductors at 23 K. They did this by chemically reducing the Cu (i.e. , doping the system with electrons) in two steps: (1) the replacement of trivalent (Nd) by tetravalent ions (Ce), and (2) the removal of oxygen. This new superconducting phase still contains CuOz planes, but the carriers are electrons (n type) and not holes (p type). The n-type charcharacter has been determined by Hall and Seebeck measurements , ' and x-ray absorption measurements" on polycrystalline samples indicate the presence of Cu+ scaling with Ce. Additional evidence supporting n-type conductivity in these new electron-doped superconductors is that the replacement of oxygen by fluorine (i.e. , again a reduction of the Cu) also induces superconductivity. ' By replacing the Nd in the parent compound Nd2, Ce"Cu04by other rare earths (Pr, Sm, Eu), and the Ce by Th, additional new n-type superconducting phases have been synthesized. ' '

Research paper thumbnail of Anomalous hysteresis in the Josephson plasma resonance of Bi2Sr2CaCuO8+δ for fields close to alignment with the ab plane

Research paper thumbnail of Out-of-plane conductivity in single-crystal YBa_{2}Cu_{3}O_{7}

Physical Review B, 1988

The resistivity anisotropy has been measured in seven single crystals of YBa2Cu307. %e 6nd that t... more The resistivity anisotropy has been measured in seven single crystals of YBa2Cu307. %e 6nd that the anisotropy is between 56 and 110 at 290 K, increasing to -250 just above T, (90-93 K). While the out-of-plane resistivity p, is close to the Mott limit, the large in-plane ...

Research paper thumbnail of Anomalous in-plane paraconductivity in single-crystal YBa_{2}Cu_{3}O_{7}

Physical Review B, 1988

We have studied the in-plane paraconductivity in single crystals of YBa2Cu3O7 with exceptionally ... more We have studied the in-plane paraconductivity in single crystals of YBa2Cu3O7 with exceptionally sharp transitions. For temperatures greater than ~1 K above the transition temperature Tc, we find good qualitative and some quantitative agreement with the two-dimmensional Aslamazov-Larkin theory. The jump to zero resistance occurs in a narrow interval of less than 0.5 K. Our data are inconsistent with the Lawrence-Doniach expression for crossover from two to three dimensions.

Research paper thumbnail of Mid-infrared reflectivity and ellipsometry measurements on single-crystal YBa2Cu3O7 and Bi2Sr2CuO6+y

Research paper thumbnail of Phase-plot studies of the alternating charge-density-wave current in niobium triselenide

Physical Review B, 1985

Phase plots of ICDW (the charge-density-wave current) versus the applied electric field E are pre... more Phase plots of ICDW (the charge-density-wave current) versus the applied electric field E are presented for driving frequencies 300 kHz to 3 MHz in NbSe3. When E exceeds the threshold value, inductive behavior (I lags E) appears. The strong hysteresis observed is inconsistent with the single-oscillator model. We compare the results with predictions of the overdamped pendulum equation and the transient overshoot phenomenon.

Research paper thumbnail of Nonlinear ac dynamics of charge-density-wave condensate in NbSe_{3}

Physical Review B, 1983

Phase-space plots of the ac charge-density-wave (CDW) current versus the ac voltage have been obt... more Phase-space plots of the ac charge-density-wave (CDW) current versus the ac voltage have been obtained in NbSe3 for frequencies 0.1-5 MHz. The strong inductive hysteresis observed is consistent with metastable states in the CDW and incompatible with classical oscillator models.