ZincSun commented 3 years ago

Abstract

The theory of open quantum system supports most modern research in quantum mechanics and its applications in many areas. In this project, we would like to design an algorithm which utilize the noise on IBMQ system to simulate an open quantum system. We hope that our result could pave the way to a new perspective of quantum simulation.

Description

Simulation of a quantum system has been a "Holy Grail" problem in science since the dawn of quantum physics. In fact, the original proposal for the quantum computer by Richard Feynman was to make an controllable quantum system to simulate another one. To our understanding, universal quantum computers promise to revolutionize computations in several areas highly related to chemistry due to their the exponentially large state space, quantum parallelism, and the power of entanglement. Several quantum algorithms for problems in chemistry have been proposed, for example, the Phase Estimation Algorithm (PEA) for calculating ground state energy for molecules.

However, contemporary quantum computers suffer from severe errors, termed as Noisy Intermediate-Scale Quantum (NISQ), which render long quantum circuits useless for practical purposes. To utilize near term NISQ computers, we must find suitable problems and design efficient quantum algorithms to demonstrate their supremacy. Hence, in our project, we intend to characterize the intrinsic noises in current quantum computers and try to utilize the noises to simulate a open quantum system.

The model system we choose is an exciton model for excitation energy transfer, which is often employed to describe energy transfer process in semiconductor or light-harvesting complex in photosynthetic organism. We would like to simulate the process in a dissipative environment on IBMQ system, which we believe could provide more insight into the dynamics of open quantum systems, non-equilibrium statistical mechanics in general, and help develop better devices.

Our goals: 1. Design algorithms to introduce controllable noise into the quantum system. 2. Set up evolution circuit for our modeled system and test them on the IBMQ system. 3. Interpret the result of our quantum simulation physically.