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Magnetoresistance. Linear-MR Xu et al., Nature 390, 57 ’97 The LMR is a classical effect associated with macroscopic non-homogeneities . Its strength scales with the electron mobility. Negative-MR Ashuler et al., PRB 22, 5142 ’80
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Magnetoresistance • Linear-MR • Xu et al., Nature 390, 57 ’97 • The LMR is a classical effect associated with macroscopic non-homogeneities. Its strength scales with the electron mobility. • Negative-MR • Ashuler et al., PRB 22, 5142 ’80 • The NMR is a quantum effect due to weak-localization. The minimum of the MR occurs when the magnetic length (e/hB)1/2 becomes equal to 2lj, where lj ~ 100nm is the electron coherence length. InAs1-xNx T=2K Patanè et al. PRB 80 115207 ’09
Comparing III-N-Vs InAsN Eg-G = 1.42 eV EL~0.3 eV EX~0.3 eV GaAsN Eg-G = 0.35 eV EL=1.08 eV EX=1.37 eV Energy Energy X-valley X-valley G-valley G-valley L-valley L-valley N N <100> <111> <100> <111> Wave vector The energy of the N-level (EN~ 1eV) is larger than the threshold energy for impact ionization (~ Eg-G). The energy of the N-level (EN~ 0.2eV) is smaller than the threshold energy for impact ionization (~ Eg-G).
GaAsN: RELIEF-effect Resonant Electron Localization In Electric Field e GaAs Γ X L N k Balance between the resonant localization of electrons at N-levels and scattering phenomena leads to Negative Differential Resistance. PRL 91, 126802 ’03 APL 88 032107 ’06 JPCM 21, 174209 ’09 See also theory-work of J. Rorison and N. Vogiatzis (Un. Bristol, UK)
