Abstract: This disclosure provides systems, methods, and apparatus related to semiconductor photomultipliers. In one aspect, a device includes a p-type semiconductor substrate, the p-type semiconductor substrate having a first side and a second side, the first side of the p-type semiconductor substrate defining a recess, and the second side of the p-type semiconductor substrate being doped with n-type ions. A conductive material is disposed in the recess. A p-type epitaxial layer is disposed on the second side of the p-type semiconductor substrate. The p-type epitaxial layer includes a first region proximate the p-type semiconductor substrate, the first region being implanted with p-type ions at a higher doping level than the p-type epitaxial layer, and a second region disposed on the first region, the second region being doped with p-type ions at a higher doping level than the first region.

Abstract: A gas turbine engine is provided comprising a compressor, a fuel supply apparatus, a combustor, and a turbine. The fuel supply apparatus comprises a fuel source, a cooling apparatus including a heat exchanger and structure for defining a first path for fuel to travel from the fuel source to the heat exchanger and a second path for fuel to travel away from the heat exchanger. The combustor functions to receive the compressed air from the compressor and the fuel from the heat exchanger, combine the air and fuel to create an air/fuel mixture and ignite the air/fuel mixture to create combustion products. The cooling apparatus further comprises structure coupled to and extending between the heat exchanger and at least one of a plurality vanes in the turbine for circulating a coolant fluid through at least one vane and the heat exchanger. In another embodiment, pipe supply structure extends from a fuel source through an end section of a turbine casing.

Abstract: A gas turbine engine is provided comprising a compressor, a fuel supply apparatus, a combustor, and a turbine. The fuel supply apparatus comprises a fuel source, a cooling apparatus including a heat exchanger and structure for defining a first path for fuel to travel from the fuel source to the heat exchanger and a second path for fuel to travel away from the heat exchanger. The combustor functions to receive the compressed air from the compressor and the fuel from the heat exchanger, combine the air and fuel to create an air/fuel mixture and ignite the air/fuel mixture to create combustion products. The cooling apparatus further comprises structure coupled to and extending between the heat exchanger and at least one of a plurality vanes in the turbine for circulating a coolant fluid through at least one vane and the heat exchanger. In another embodiment, pipe supply structure extends from a fuel source through an end section of a turbine casing.