HiPER – AWG & sensitivity
The HiPER spectrometer was originally developed under the EPSRC Basic Technology programme. It operates at 94 GHz with an instantaneous bandwidth of 1 GHz at power levels above 1 kW, which typically allows 6 ns π/2 pulses with large volume samples. It was recently upgraded with new low noise detection amplifiers, an upgraded digitiser, and is controlled by an Agilent M8190A Arbitrary Waveform Generator (AWG), which features digital IQ up-conversion. This allows shaped pulses in both amplitude and phase to be implemented with extremely low levels of spurii and harmonics. This improves both excitation bandwidth and the selectivity of pulses. Low Q, large volume sample holders allow the full 1 GHz bandwidth to be exploited, or alternatively bandwidth can be traded off for more sensitivity around a central frequency. Bespoke software allows easy control of a wide range of experiments. The result is a flexible instrument that has significantly higher concentration sensitivity than the best commercial instruments for most common measurements.
Bespoke software allows considerable flexibility in setting up experiments, allowing a wide variety of shaped pulses and phase-cycling schemes.
The spectrometer has very high concentration sensitivity with respect to conventional commercial spectrometers.