Far-infrared optical properties of superconducting Bi sub 2 Sr sub 2 CaCu sub 2 O sub x films

Journal Article · Sun Jul 01 04:00:00 EDT 1990 · Physical Review, B: Condensed Matter; (USA)

DOI:https://doi.org/10.1103/PhysRevB.42.193· OSTI ID:6563881

Rao, A M; Eklund, P C; Lehman, G W ^[1]; Face, D W ^[2]; Doll, G L ^[3]; Dresselhaus, G ^[4]; Dresselhaus, M S ^[5]

---

1. Department of Physics and Astronomy, University of Kentucky, Lexington, KY (USA)
2. Center for Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA (USA)
3. Department of Physics, Massachusetts Institute of Technology, Cambridge, MA (USA)
4. Francis Bitter National Magnet Laboratory, Massachusetts Institute of Technology, Cambridge, MA (USA)
5. Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA (USA) Department of Physics, Massachusetts Institute of Technology, Cambridge, MA (USA)

The optical reflectance of thin superconducting Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub {ital x}} (Bi 2:2:1:2) films has been studied in the frequency range 80--48 000 cm{sup {minus}1} and the temperature range 5 K{lt}{ital T}{lt}300 K. Since the film thickness {ital d} is less than the optical skin depth {delta}, the reflectance from the film-substrate (SrTiO{sub 3}) interface must be considered in the interpretation of the experimental results. The dielectric function of the superconductor is calculated with use of the model of Leplae, which takes into account the effect of the quasiparticle lifetime. Structure in the reflectivity spectra is identified with Bi 2:2:1:2 phonons, SrTiO{sub 3} substrate phonons, and for {ital T}{lt}{ital T}{sub {ital c}}, evidence for a superconducting gap is observed. The gap at {ital T}=5 K was found to be 2{Delta}=35{plus minus}5 meV {congruent}6{ital k}{sub {ital B}T{ital c}}, in good agreement with previous tunneling studies.

• DOE Contract Number: FG05-84ER45151
• OSTI ID: 6563881
• Journal Information: Physical Review, B: Condensed Matter; (USA), Journal Name: Physical Review, B: Condensed Matter; (USA) Vol. 42:1; ISSN 0163-1829; ISSN PRBMD
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360603* -- Materials-- Properties
ALKALINE EARTH METAL COMPOUNDS
BISMUTH COMPOUNDS
BISMUTH OXIDES
CALCIUM COMPOUNDS
CALCIUM OXIDES
CHALCOGENIDES
COPPER COMPOUNDS
COPPER OXIDES
DIELECTRIC TENSOR
ELECTROMAGNETIC RADIATION
ENERGY GAP
FAR INFRARED RADIATION
FILMS
FREQUENCY DEPENDENCE
HIGH-TC SUPERCONDUCTORS
INFRARED RADIATION
LOW TEMPERATURE
MEDIUM TEMPERATURE
OPTICAL PROPERTIES
OXIDES
OXYGEN COMPOUNDS
PHONONS
PHYSICAL PROPERTIES
QUASI PARTICLES
RADIATIONS
REFLECTIVITY
STRONTIUM COMPOUNDS
STRONTIUM OXIDES
SUPERCONDUCTING FILMS
SUPERCONDUCTORS
SURFACE PROPERTIES
TEMPERATURE DEPENDENCE
TENSORS
TRANSITION ELEMENT COMPOUNDS
ULTRALOW TEMPERATURE
VERY LOW TEMPERATURE