Numerical Simulation of multi-junction bias circuits for superconducting detectors

We present numerical simulations of a new biasing circuit for single photon detectors based on superconducting tunnel junctions. A single detector junction is replaced with a circuit of three junctions to achieve biasing of a detector junction at subgap currents without the use of an external magnetic field. The biasing occurs through the nonlinear interaction of the three junctions. We show nonlinear numerical simulation for different values of junction parameters and demonstrate that the biasing state is numerically stable against external fluctuations. The elimination of the external magnetic field potentially increases the capability of these types of photon detectors and eases constraints involved in the fabrication of large detector arrays.