Phonon emission at the center of Quantum Hall plateaus

We measure the diagonal conductivity, sigma(xx), of a 2DEG as a function of varied applied voltage at integer filling factors (v) in the quantum Hall effect. In the context of electron heating, we find that at odd integer v the phonon emission rate tau(e-p)(-1) = 1.44 +/- 0.23 x 10(8) T-3 s(-1), comparable to Price's calculation {[}J. Appl. Phys. 53 (1982) 6863] while it is about 10 times smaller at even integer v. (C) 1999 Elsevier Science Ltd. All rights reserved.