Thermally coupled imager for performing time and position sensitive imaging of single photons

A thermally coupled imager for performing time and position sensitive imaging of single photons, the thermally coupled imager comprising:

• a single photon detection pixel comprising:
• a superconducting nanowire single photon detector that receives an electrical current bias and that, in response to receiving a single photon, transitions from a superconducting state via heating;
• and
• a resistive heater in electrical communication with the superconducting nanowire single photon detector and electrically connected in parallel with the superconducting nanowire single photon detector, such that when the single photon is received by the superconducting nanowire single photon detector:
• the electrical current bias is diverted from being received by the superconducting nanowire single photon detector and is electrically communicated to the resistive heater;
• the resistive heater converts the electrical current bias into thermal energy, and the thermal energy is thermally communicated to a thermally conductive galvanic isolator;
• the thermally conductive galvanic isolator in thermal communication with the resistive heater and a thermal readout bus, such that the thermally conductive galvanic isolator receives the thermal energy from the resistive heater, electrically isolates the single photon detection pixel from the thermal readout bus, and thermally communicates the thermal energy from the resistive heater to the thermal readout bus in an absence of electrical crosstalk between the single photon detection pixel and the thermal readout bus;
• and
• the thermal readout bus in thermal communication with the thermally conductive galvanic isolator and in electrical isolation with the single photon detection pixel and comprising:
• a superconducting nanowire;
• a thermal detection portion disposed proximate to the resistive heater in thermal communication with the thermally conductive galvanic isolator;
• a total length L between a first terminus and a second terminus, such that:
• the thermal readout bus receives an electrical current readout bias,
• the thermal detection portion is interposed between the first terminus and the second terminus and arranged at a first distance L1 from the first terminus and a second distance L2 from the second terminus;
• the thermal detection portion receives the thermal energy from the resistive heater via the thermally conductive galvanic isolator,
• in response to receiving the thermal energy, the thermal detection portion transitions from a superconducting state and produces a pair of voltage pulses from the electrical current readout bias that propagate in the thermal readout bus away from the thermal detection portion, such that one voltage pulse propagates from the thermal detection portion toward the first terminus during a first time-of-flight period, and the other voltage pulse propagates from the thermal detection portion toward the second terminus during a second time-of-flight period,
• wherein the pair of voltage pulses, the first time-of-flight period, and the second time-of-flight period provide a time of arrival and position of the single photon received by the single photon detection pixel;
• a second single photon detection pixel arranged along the thermal readout bus and electrically isolated from the single photon detection pixel;
• the thermal readout bus comprises a second thermal detection portion disposed proximate to the second single photon detection pixel and in thermal communication with the second single photon detection pixel via the thermally conductive galvanic isolator that electrically isolates the thermal readout bus and the single photon detection pixel, wherein:
• the second single photon detection pixel receives a second single photon and produces thermal energy in response to receipt of the second single photon, and
• the second thermal detection portion of the thermal readout bus receives the thermal energy from the second single photon detection pixel, transitions from the superconducting state, and produces a second pair of voltage pulses that correspond to a position of the second single photon detection pixel along the thermal readout bus,
• such that of the second pair of voltage pulses:
• one voltage pulse propagates from the second thermal detection portion toward the first terminus during a third time-of-flight period, and the other voltage pulse propagates from the second thermal detection portion toward the second terminus during a fourth time-of-flight period, and
• the second pair of voltage pulses, the third time-of-flight period, and the fourth time-of-flight period provide a time of arrival and position of the second single photon detection pixel that received the second single photon;
• and
• additional single photon detection pixels, such that each additional single photon detection pixel:
• is disposed proximate to and in thermal communication with individual thermal detection portions of the thermal readout bus,
• is electrically isolated from the other single photon detection pixels and the thermal readout bus, and
• produces, in response to receiving a single photon, thermal energy that is communicated to the thermal readout bus at its respective thermal detection portion that produces pairs of voltage pulses in response to receiving the thermal energy that propagate separately toward the first terminus and the second terminus for determination of a time of arrival and position of the particular single photon detection pixel that received the respective single photon,
• wherein the single photon detection pixel, the second single photon detection pixel, and the additional single photon detection pixel are arranged in a non-linear array format and perform multidimensional imaging of single photons received by the thermally coupled imager.