Stim: a fast stabilizer circuit simulator

This paper presents “Stim", a fast simulator for quantum stabilizer circuits. The paper explains how Stim works and compares it to existing tools. With no foreknowledge, Stim can analyze a distance 100 surface code circuit (20 thousand qubits, 8 million gates, 1 million measurements) in 15 seconds and then begin sampling full circuit shots at a rate of 1 kHz. Stim uses a stabilizer tableau representation, similar to Aaronson and Gottesman's CHP simulator, but with three main improvements. First, Stim improves the asymptotic complexity of deterministic measurement from quadratic to linear by tracking the inverse of the circuit's stabilizer tableau. Second, Stim improves the constant factors of the algorithm by using a cache-friendly data layout and 256 bit wide SIMD instructions. Third, Stim only uses expensive stabilizer tableau simulation to create an initial reference sample. Further samples are collected in bulk by using that sample as a reference for batches of Pauli frames propagating through the circuit.

Fault-tolerant magic state preparation with flag qubits

Magic state distillation is one of the leading candidates for implementing universal fault-tolerant logical gates. However, the distillation circuits themselves are not fault-tolerant, so there is additional cost to first implement encoded Clifford gates with negligible error. In this paper we present a scheme to fault-tolerantly and directly prepare magic states using flag qubits. One of these schemes requires only three ancilla qubits, even with noisy Clifford gates. We compare the physical qubit and gate cost of our scheme to the magic state distillation protocol of Meier, Eastin, and Knill (MEK), which is efficient and uses a small stabilizer circuit. For low enough noise rates, we show that in some regimes the overhead can be improved by several orders of magnitude compared to the MEK scheme which uses Clifford operations encoded in the codes considered in this work.

Rancang Bangun Penstabil Tegangan pada Pembangkit Termoelektrik Skala Pico Berbasis Boost Converter

Least of using thermoelectric module as an electric generator in society was often because of energy which was produced by it was unstable. So we need voltage stabilizer circuit to push up and down the voltage to certain voltage. The purpose of this final project is to design a voltage stabilizer circuit in pico scale DC voltage based on boost converter. This experiment is done by three stage there are, stabilizer experiment by adaptor, performance of thermoelectric generator and also stabilizer experiment by thermoelectric generator.The yield of the first experiment, when we gave input voltage 3 until 9 V produced 5,07 until 5,08 V, so it has 98,55% accuracy toward 5 V expect. On the second experiment, when it is given by ∆T 30, 50 and 70 °C produced 2,5, 3,04 and 3,39 V. While on third experiment, with the same ∆T produced 5,08 until 5,09 V. But, when ∆T which given by 12 °C produced only 0,8 and 0,9 V in second and third experiment, it is because of the voltage is not fulfill accupation voltage 2 until 24 V on datasheet of used IC. Relation between ∆T and Voltage (V), Current (I) also Power (P) which was produced have positive R value 0,76 until 1, this mean that ∆T directly proportional to V,I and P. So, the higher ∆T we give, the higher V, I and P will be.Keywords : stabilizer, thermoelectric, boost converter.