Photonics Letters of Poland

Detection of THz nanosecond pulses by fast Hot Electron Bolometer

Norbert Pałka, Przemysław Zagrajek, Adam Czerwiński, Tomasz Trzcinski, Elzbieta Rurka, M. Szustakowski, Maciej Sypek

Published Sep 30, 2012• 3 citations

Abstract

Detection of about 20 ns pulses by fast and sensitive NbN-based Hot Electron Bolometer is reported. The pulses were generated by an Optical Parametric Oscillator operating in non-collinear, intersecting cavity configuration. We present details of the oscillator and bolometer as well as a measurement setup. Linearity of the system was measured and agrees well with theoretical considerations. Full Text: PDF References L. Yun-Shik, Principles of Terahertz Science and Technology (Springer, 2008). E.F. Plinski, Bull. Pol. Ac.: Tech. 58, 463 (2010). DirectLink Firefly-THz User Manual (M Squared Lasers Ltd, 2011). A. Sato et al., "Tabletop terahertz-wave parametric generator using a compact, diode-pumped Nd:YAG laser", Rev. Sci. Instrum. 72, 3501 (2001). CrossRef N. Palka et al., Proc. of MIKON 2012, 265 (2012). Scontel, Superconducting Nanotechnology, HEB User Manual. A.D. Semenov et al., "Design and performance of the lattice-cooled hot-electron terahertz mixer", J.App. Phys. 88, 1 (2000). CrossRef

DOI: 10.4302/plp.2012.3.08

Related papers

NbN hot electron bolometric mixers-a new technology for low-noise THz receivers

Eyal Gerecht, Charles F. Musante, Yan Zhuang +4 more

New advances in hot electron bolometer (HEB) mixers have recently resulted in record-low receiver noise temperatures at terahertz frequencies. We have developed quasi-optically coupled NbN HEB mixers and measured noise temperatures up to 2.24 THz, as described in this paper. We project the anticipated future performance of such receivers to have even lower noise temperature and local-oscillator power requirement as well as wider gain and noise bandwidths. We introduce a proposal for integrated focal plane arrays of HEB mixers that will further increase the detection speed of terahertz systems.

IEEE Transactions on Microwave Theory and TechniquesJan 1, 199939 citations

Microwave probing of relaxation oscillations related to terahertz power detection in superconducting hot electron bolometers

Runfeng Su, Y D Zhang, Xuecou Tu +8 more

Abstract Relaxation oscillations related to terahertz (THz) power detection in superconducting niobium nitride hot electron bolometers (HEBs) have been studied using microwaves as a probe. The reflected microwave signal, which is related to the impedance changes of the HEB irradiated by an incident THz signal, can be used to characterize relaxation oscillations. The frequency of relaxation oscillation switching between the superconducting and resistive states increases linearly with incident THz power but nonlinearly with bias voltage or bath temperature. The observed strong periodic pulse trains of relaxation oscillations have a maximum duty cycle of ∼50%. These strong switching pulses indicate that DC Joule heating, THz radiation or thermal energy is absorbed in the bi-stable region of the HEB intermittently. In addition to relaxation oscillations, we also see weaker oscillations when the device is in the resistive state, which we call intrinsic oscillations. These have a constant frequency at the order of 10 kHz which is independent of external stimuli. The weak periodic pulse trains at a constant frequency can be divided into mainly two types—one is the pulse train with a small duty cycle and the other is the quasi-square wave. Measurement of these oscillations in HEBs has some practical applications. Digital THz power measurement with frequencies below and above the gap frequency can be made based on the linearity between relaxation oscillation frequency and incident THz power. The relaxation oscillation frequency can be used to estimate the maximum speed of a THz direct detection system especially for a multi-pixel HEB array. In particular, extra noise induced by relaxation oscillations and intrinsic oscillations can be determined for the HEB operating as a THz direct detector.

Superconductor Science and TechnologyJul 9, 20196 citations

Terahertz Power Detectors based on Superconducting HEBs with Microwave Readout

Runfeng Su, J. Chen, Peiheng Wu +8 more

The properties of terahertz (THz) power detectors based on Superconducting NbN hot electron bolometer (HEB) with microwave (MW) readout are reported here. Features of relaxation oscillations probed with MW when the HEB is not pumped, pumped by THz source or heated by raising the bath temperature are studies. The periodic pulse in the reflected MW signals both in time and frequency domains show that the relaxation oscillation frequency increases with the bias voltage, incident THz power and/or bath temperature. The frequency count forms a quadratic polynomial fit to the bias voltage, a linear fit to the incident THz power and an exponential fit to the bath temperature. Based on the above results, incident THz power between 8-90 nW is measured using the HEB.

IEEE International Superconductive Electronics Conference (ISEC)Jul 1, 20190 citations

Heterodyne measurements of a NbN superconducting hot electron mixer at terahertz frequencies

Pavel A. Yagoubov, M. Kroug, H. Merkel +6 more

The performance of a NbN based phonon-cooled Hot Electron Bolometric (HEB) quasioptical mixer is investigated in the 0.65-3.12 THz frequency range. The device is made from a 3 nm thick NbN film on high resistivity Si and integrated with a planar spiral antenna on the same substrate. The in-plane dimensions of the bolometer strip are 0.2/spl times/2 /spl mu/m. The best results of the DSB noise temperature at 1.5 GHz IF frequency obtained with one device are: 1300 K at 650 GHz, 4700 K at 2.5 THz and 10000 K at 3.12 THz. The measurements were performed at 4.5 K ambient temperature. The amount of local oscillator (LO) power absorbed in the bolometer is about 100 nW. The mixer is linear to within 1 dB compression up to the signal level 10 dB below that of the LO. The intrinsic single sideband conversion gain measured at 650 GHz is -9 dB, the total conversion gain is -14 dB.

IEEE Transactions on Applied SuperconductivityJun 1, 19996 citations

Superconducting NbN hot electron bolometer mixer at terahertz

Biaobing Jin, Jianhui Chen, Min Liang +3 more

Superconducting niobium nitride (NbN) hot electron bolometer (HEB) mixers at terahertz (THz) have been designed, fabricated and measured for applications in astronomy and cosmology. The NbN HEB mixer consists of a planar antenna and an NbN bridge connecting across the antenna's inner terminals on high-resistivity Si substrates. Double sideband (DSB) receiver noise temperatures of 698 K at 0.65 THz, 904 K at 1.6 THz, 1026 K at 2.5 THz and 1386 K at 3.1 THz have been obtained at 4.2 K without corrections and using changeable input local oscillation (LO) power to eliminate the affects of direct detection and instability of the LO power. The excess quantum noise factor beta of about 4 has been estimated using a quantum noise model.

International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz)Sep 1, 20090 citations

Development of terahertz superconducting hot-electron bolometer mixers

Andrew G. Semenov, Heiko Richter, H.-W. Hübers +3 more

We present recent results of the development of phonon cooled hot-electron bolometric (HEB) mixers for airborne and balloon borne terahertz heterodyne receivers. Three iomportant issues have been addresses: the quality of NbN films the HEB mixers were made from, the spectral properties of the HEB mixers and the local oscillator power required for optical operation. Studies with an atomic force microscope indicate, that the performance of the HEB mixer might have been effected by the microstructure of the NbN film. Antenna gain and noise temperature were investigated at terahertz frequencies for a HEB embedded in either log-spiral or twin-slot feed antenna. Comparison suggests that at frequencies above 3 THz the spiral feed provides better overall performance. At 1.6 THz, a power of 2.5 µW was required from the local oscillator for optimal operation of the HEB mixer.

Jan 1, 20040 citations