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We present a systematic study of the temperature dependence of the electrical noise in a quantum dot, optically gated, field-effect transistor (QDOGFET) and detail how the noise influences the sensitivity of these novel single-photon detectors. Previous studies have shown that when cooled to 4 K, QDOGFETs exhibit single-photon sensitivity and photon-number-resolving capabilities; however, there has been no systematic study of how operating temperature affects their performance. Here, we measure the noise spectra of a device for a range of sample temperatures between 7 K and 60 K. We use the noise data to determine the signal-to-noise ratio of the optical responses of the devices for various temperatures and detection rates. Our analysis indicates that QDOGFETs can operate over a broad range of temperatures, where increased operating temperature can be traded for decreased sensitivity.

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Executive SummaryThe goal of this year's collegiate rocket competition was to design and successfully launch a one-stage, high-powered rocket that, during its ascent, would transmit live video from a downward looking camera to a ground based receiver. In order to be considered a successful launch, the rocket was to attain an altitude near 3000 feet, electronically deploy a recovery parachute attached to all parts of the rocket, succeed in transmitting live video throughout the ascent, and safely land in a flyable condition.To achieve these requirements, the UWL Physics Rocket Team used OpenRocket to sketch a design that best fit the specifications of the competition. After it was discovered that programs such as OpenRocket are capable of doing the brunt of the theoretical work, it was decided that the majority of the essential components of our rocket would be hand built to increase the feeling of personal accomplishment. The design of our rocket utilizes a dual deployment recovery system, with the bottom section housing a custom made motor mount, the middle section housing the electronics for recording flight data, and the top-most section housing the equipment for the recording and transmitting of live video. Design FeaturesRocket design. The design of the rocket began with meeting the requirement of lifting a payload to 3000 ft (915 m) simply and efficiently. After researching the basic elements of rocket design and construction, a single minimum diameter, dual deployment type was selected. Upon receiving the list of motors available and reviewing initial flight simulations, we found that the J357 38mm motor was best suited to reaching the target altitude. Based on the size of the video system components, a 98mm (4in) diameter blue tube airframe was chosen. The rocket design consists of four sections, the nosecone and payload bay, the main recovery bay, the flight electronics bay and the booster with drogue chute.The nosecone is an ogive shape and is fastened to the airframe with removable plastic rivets. The video system is housed just below the nosecone on a removable sled constructed from 3/16 inch plywood and 1/2 inch plywood bulkheads. The payload bay uses as little metal as possible, to keep inference with the transmission antenna at a minimum. The rear bulkhead of the sled holds an eye-bolt serving as the forward attachment point of the main parachute recovery harness. The payload sled is held inside the airframe between the nosecone and a glued in blue tube coupler.Continuing downward, the main recovery bay holds the main parachute, a Top Flight Recovery 60 in. Crossfire nylon parachute and a 9 meter 1 in. tubular nylon recovery harness. The aft attachment point for the harness is the electronics bay. The e-bay is built from a blue tube coupler and two 1/2 inch plywood bulkheads connected with 1/4 inch threaded rods. A sled for the altimeter, battery, arming switches and flight data recorder is attached to the rods. The e-bay serves as the central structure of the rocket and all components are tethere...