PT Journal AU Kooi, JW Baselmans, JJA Hajenius, M Gao, JR Klapwijk, TM Dieleman, P Baryshev, A de Lange, G TI IF impedance and mixer gain of NbN hot electron bolometers SO J. Appl. Phys. PY 2007 BP 044511 VL 101 IS 4 DI 10.1063/1.2400086 ER