Scanning tunneling microscopy of atoms and charge-density waves in 1 T -TaS sub 2 , 1 T -TaSe sub 2 , and 1 T -VSe sub 2

Journal Article · Tue May 15 04:00:00 EDT 1990 · Physical Review, B: Condensed Matter; (USA)

DOI:https://doi.org/10.1103/PhysRevB.41.10082· OSTI ID:6880180

Giambattista, B; Slough, C G; McNairy, W W; Coleman, R V ^[1]

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1. Department of Physics, University of Virginia, Charlottesville, VA (USA)

The surface atomic structure and the charge-density-wave (CDW) structure in the 1{ital T} phase of TaSe{sub 2}, TaS{sub 2}, and VSe{sub 2} have been studied at 4.2, 77, and 300 K. The response of the scanning tunneling microscope (STM) to the CDW superlattice in 1{ital T}-TaSe{sub 2} and 1{ital T}-TaS{sub 2} is extremely strong, while in 1{ital T}-VSe{sub 2} the CDW generates a much weaker response. In 1{ital T}-TaSe{sub 2} and 1{ital T}-TaS{sub 2} at 4.2 and 77 K the STM scans show a {radical}13 {bold a}{sub 0}{times} {radical}13 {bold a}{sub 0} pattern characteristic of a triple-{bold q} commensurate CDW structure. The atomic lattice and CDW superlattice are simultaneously resolved, but the atomic modulation represents a small fraction of the total STM deflection leading to a substantial variation in the atomic resolution. At 300 K we continue to observe a commensurate {radical}13 {bold a}{sub 0}{times} {radical}13 {bold a}{sub 0} CDW pattern in 1{ital T}-TaSe{sub 2} while 1{ital T}-TaS{sub 2} shows a modulated two-dimensional structure due to the incommensurate CDW wavelength characteristic of the nearly commensurate phase.

• DOE Contract Number: FG05-84ER45072
• OSTI ID: 6880180
• Journal Information: Physical Review, B: Condensed Matter; (USA), Journal Name: Physical Review, B: Condensed Matter; (USA) Vol. 41:14; ISSN PRBMD; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360603* -- Materials-- Properties
CHALCOGENIDES
COHERENT SCATTERING
CRYSTAL DEFECTS
CRYSTAL STRUCTURE
DIFFRACTION
ELECTRON DIFFRACTION
ELECTRON MICROSCOPY
ELECTRONIC STRUCTURE
ENERGY LEVELS
FERMI LEVEL
FUNCTIONS
LOW TEMPERATURE
MEDIUM TEMPERATURE
MICROSCOPY
POINT DEFECTS
REFRACTORY METAL COMPOUNDS
SCANNING ELECTRON MICROSCOPY
SCATTERING
SELENIDES
SELENIUM COMPOUNDS
SULFIDES
SULFUR COMPOUNDS
SUPERLATTICES
SURFACE PROPERTIES
TANTALUM COMPOUNDS
TANTALUM SELENIDES
TANTALUM SULFIDES
TEMPERATURE DEPENDENCE
TRANSITION ELEMENT COMPOUNDS
ULTRALOW TEMPERATURE
VACANCIES
VANADIUM COMPOUNDS
VANADIUM SELENIDES
WORK FUNCTIONS