Abstract-Te inclusions existing at high concentrations in CdZnTe (CZT) material can degrade the performance of CZT detectors. These microscopic defects trap the free electrons generated by incident radiation, so entailing significant fluctuations in the total collected charge and thereby strongly affecting the energy resolution of thick (long-drift) detectors. Such effects were demonstrated in thin planar detectors, and, in many cases, they proved to be the dominant cause of the low performance of thick detectors, wherein the fluctuations in the charge losses accumulate along the charge's drift path. We continued studying this effect using different tools and techniques. We employed a dedicated beam-line recently established at BNL's National Synchrotron Light Source for characterizing semiconductor radiation detectors, along with an IR transmission microscope system, the combination of which allowed us to correlate the concentration of defects with the devices' performances. We present here our new results from testing over 50 CZT samples grown by different techniques. Our goals are to establish tolerable limits on the size and concentrations of these detrimental Te inclusions in CZT material, and to provide feedback to crystal growers to reduce their numbers in the material.

Hybrid distributed Raman-EDFA amplifiers, with a continuous 91 nm gain bandwidth and 1.4 dB average effective noise figure, are used to enable a record single mode fibre transmission capacity of 120 Tbit/s using 312×35 GBd DP-256QAM over 9×70 km spans.

We experimentally demonstrated the transmission of 312⇥35 GBd DP-256QAM over 9⇥70 km spans using hybrid distributed Raman-EDFA (HRE) amplifiers with a continuous 91 nm gain bandwidth. A total throughput of 120 Tbit/s over 630 km is demonstrated, with a net achievable information rate after SD-FEC of 10.99 bit/symbol. An extensive, theoretical investigation of the noise contributions originating from amplifier, transceiver sub-system and fiber nonlinearity were carried out using the Gaussian noise model in the presence of inter-channel stimulated Raman scattering (ISRS GN model). The ISRS GN model accounts for arbitrary, wavelength dependent signal power profiles along fiber spans, which is vital for the modeling of ultra-wideband transmission, particularly for hybrid Ramanamplified links. The analysis serves to quantify the relative noise contributions and explain the performance achieved. It was found that, due to the low noise HRE amplifier and a transmission distance of 630 km, the noise originating from the transceiver sub-system imposed a penalty of 6 dB in SNR. For this system, the transceiver noise is, therefore, the main limitation to the system throughput.Index Terms-Hybrid Raman-EDFA amplifier, broadband transmission system, high order modulation format, adaptive rate LDPC decoder.

Abstract-Index Terms-Millimeter-wave over fiber system, DWDM thin film filter, optical phase modulator.

Abstract-We report on a low cost technique for the photonic generation of wideband continuously tunable millimeter-wave local oscillator signals. It is based on side band filtering using an optical phase modulator and thin film DWDM filters. The generated millimeter-wave signal exhibits low phase noise, and its frequency covers the Wand F-bands, from 75 GHz to 140 GHz.