Center transformation of Te donors in GaSb under hydrostatic pressure Article uri icon

abstract

  • We have observed the transformation of Te shallow donors in GaSb into (Formula presented) centers at hydrostatic pressures of (Formula presented) The position of the Te (Formula presented) energy level at zero pressure is calculated to lie (Formula presented) above the conduction band at atmospheric pressure, consistent with the theory that in the III-V compounds the (Formula presented) centers line up in energy with respect to the vacuum level within experimental error. This binding energy at zero pressure of the Te (Formula presented) compares well with the value of 210 meV calculated from the cation-cation bonded (Formula presented)-center model recently proposed by Park and Chadi. At pressures where the Te shallow donor into (Formula presented)-center transformation has taken place we observe evidence of the existence of a bound phonon associated with the Te (Formula presented) center. From its observed pressure dependence the LO optical phonon Grüneisen parameter is calculated to be (Formula presented). © 1998 The American Physical Society.

publication date

  • 1998-01-01