|
|
de Lange G, Kuipers JJ, Klapwijk TM, Panhuyzen RA, van de Stadt H, de Graauw MWM. Superconducting resonator circuits at frequencies above the gap frequency. J. Appl. Phys.. 1995;77(4):1795–804.
|
|
|
|
Ganzevles WFM, Gao JR, de Korte PAJ, Klapwijk TM. Direct response of microstrip line coupled Nb THz hot-electron bolometer mixers. Appl Phys Lett. 2001;79(15):2483–5.
|
|
|
|
Jackson BD, Baryshev AM, de Lange G, Gao JR, Shitov SV, Iosad NN, et al. Low-noise 1 THz superconductor-insulator-superconductor mixer incorporating a NbTiN/SiO2/Al tuning circuit. Appl. Phys. Lett.. 2001;79(3):436.
|
|
|
|
Hajenius M, Baselmans JJA, Gao JR, Klapwijk TM, de Korte PAJ, Voronov B, et al. Improved NbN phonon cooled hot electron bolometer mixers. In: Proc. 14th Int. Symp. Space Terahertz Technol. Tucson, USA; 2003. p. 413–23.
Abstract: NbN phonon-cooled hot electron bolometer mixers (HEBs) have been realized with negligible contact resistance to Au pads. By adding either a 5 nm Nb or a 10 nm NbTiN layer between the Au and NbN, to preserve superconductivity in the NbN under the Au contact pad, superior noise temperatures have been obtained. Using DC I,V curves and resistive transitions in combination with process parameters we analyze the nature of these improved devices and determine interface transparencies.
|
|
|
|
Baselmans JJA, Hajenius M, Gao JR, Klapwijk TM, de Korte PAJ, Voronov B, et al. Doubling of sensitivity and bandwidth in phonon cooled hot electron bolometer mixers. Appl Phys Lett. 2004;84(11):1958–60.
Abstract: We demonstrate that the performance of NbN lattice cooled hot electron bolometer mixers depends strongly on the interface quality between the bolometer and the contact structure. We show experimentally that both the receiver noise temperature and the gain bandwidth can be improved by more than a factor of 2 by cleaning the interface and adding an additional superconducting interlayer to the contact pad. Using this we obtain a double sideband receiver noise temperature TN,DSB=950 K
at 2.5 THz and 4.3 K, uncorrected for losses in the optics. At the same bias point, we obtain an IF gain bandwidth of 6 GHz.
|
|
