Abstract
We have calculated the longitudinal acoustic attenuation in a type-II superconductor in high magnetic fields within a mean-field BCS theory. We predict two additional features in the corresponding attenuation signal as compared to that of the Meissner state. Our analytical calculations predict the existence of oscillations in the attenuation as the external magnetic field is varied - this effect is associated with the Landau-level structure of the electron states and is analogous to the well-known de Haas-van Alphen oscillations in the mixed state. The attenuation directly probes the quasiparticle energies; the presence of gapless points in the quasiparticle spectrum, which is characteristic of type-II superconductors at high magnetic fields, shows up in the frequency ω and temperature T dependence of the attenuation in the limit of low ω and and low T, respectively. At low T there is no analog to the discontinuity in the attenuation observed in the Meissner state when ℏω=2Δ, where A is the quasiparticle energy gap. This result opens up the possiblity of experimentally determining the existence and nature of the gapless points in the quasiparticle spectrum of a type-II superconductor in high magnetic fields.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 3051-3057 |
| Number of pages | 7 |
| Journal | Physical Review B - Condensed Matter and Materials Physics |
| Volume | 57 |
| Issue number | 5 |
| State | Published - Feb 1 1998 |
| Externally published | Yes |
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ASJC Scopus subject areas
- Condensed Matter Physics
Cite this
Acoustic attenuation in a type-II superconductor at high magnetic fields. / Bruun, G. M.; Nikos Nicopoulos, V.; Johnson, Neil F.
In: Physical Review B - Condensed Matter and Materials Physics, Vol. 57, No. 5, 01.02.1998, p. 3051-3057.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Acoustic attenuation in a type-II superconductor at high magnetic fields
AU - Bruun, G. M.
AU - Nikos Nicopoulos, V.
AU - Johnson, Neil F
PY - 1998/2/1
Y1 - 1998/2/1
N2 - We have calculated the longitudinal acoustic attenuation in a type-II superconductor in high magnetic fields within a mean-field BCS theory. We predict two additional features in the corresponding attenuation signal as compared to that of the Meissner state. Our analytical calculations predict the existence of oscillations in the attenuation as the external magnetic field is varied - this effect is associated with the Landau-level structure of the electron states and is analogous to the well-known de Haas-van Alphen oscillations in the mixed state. The attenuation directly probes the quasiparticle energies; the presence of gapless points in the quasiparticle spectrum, which is characteristic of type-II superconductors at high magnetic fields, shows up in the frequency ω and temperature T dependence of the attenuation in the limit of low ω and and low T, respectively. At low T there is no analog to the discontinuity in the attenuation observed in the Meissner state when ℏω=2Δ, where A is the quasiparticle energy gap. This result opens up the possiblity of experimentally determining the existence and nature of the gapless points in the quasiparticle spectrum of a type-II superconductor in high magnetic fields.
AB - We have calculated the longitudinal acoustic attenuation in a type-II superconductor in high magnetic fields within a mean-field BCS theory. We predict two additional features in the corresponding attenuation signal as compared to that of the Meissner state. Our analytical calculations predict the existence of oscillations in the attenuation as the external magnetic field is varied - this effect is associated with the Landau-level structure of the electron states and is analogous to the well-known de Haas-van Alphen oscillations in the mixed state. The attenuation directly probes the quasiparticle energies; the presence of gapless points in the quasiparticle spectrum, which is characteristic of type-II superconductors at high magnetic fields, shows up in the frequency ω and temperature T dependence of the attenuation in the limit of low ω and and low T, respectively. At low T there is no analog to the discontinuity in the attenuation observed in the Meissner state when ℏω=2Δ, where A is the quasiparticle energy gap. This result opens up the possiblity of experimentally determining the existence and nature of the gapless points in the quasiparticle spectrum of a type-II superconductor in high magnetic fields.
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UR - http://www.scopus.com/inward/citedby.url?scp=0542441329&partnerID=8YFLogxK
M3 - Article
AN - SCOPUS:0542441329
VL - 57
SP - 3051
EP - 3057
JO - Physical Review B-Condensed Matter
JF - Physical Review B-Condensed Matter
SN - 1098-0121
IS - 5
ER -