The paper explores the quantification of nonstabilizerness, or "magic," in random Matrix Product States (RMPS), which are a generalization of random product states with bounded entanglement. The authors demonstrate that the 2-Stabilizer Rényi Entropy of RMPS converges to that of Haar random states as \( N/\chi^2 \), where \( N \) is the system size and \( \chi \) is the bond dimension. This indicates that RMPS with modest bond dimensions exhibit similar levels of magic as generic states.
The paper introduces Clifford Enhanced Matrix Product States (CMPS), which are obtained by applying Clifford unitaries to RMPS. It is shown that CMPS can approximate 4-spherical designs with arbitrary accuracy, scaling as \( \chi^{-2} \). This suggests that combining Clifford unitaries with polynomially complex tensor network states can generate highly non-trivial quantum states.
The authors also discuss the implications of these findings for classical simulation capabilities, particularly in the context of sampling in the computational basis and computing Pauli expectation values. They highlight the potential for efficient classical simulations of many-body quantum systems and quantum circuits using CMPS representations.The paper explores the quantification of nonstabilizerness, or "magic," in random Matrix Product States (RMPS), which are a generalization of random product states with bounded entanglement. The authors demonstrate that the 2-Stabilizer Rényi Entropy of RMPS converges to that of Haar random states as \( N/\chi^2 \), where \( N \) is the system size and \( \chi \) is the bond dimension. This indicates that RMPS with modest bond dimensions exhibit similar levels of magic as generic states.
The paper introduces Clifford Enhanced Matrix Product States (CMPS), which are obtained by applying Clifford unitaries to RMPS. It is shown that CMPS can approximate 4-spherical designs with arbitrary accuracy, scaling as \( \chi^{-2} \). This suggests that combining Clifford unitaries with polynomially complex tensor network states can generate highly non-trivial quantum states.
The authors also discuss the implications of these findings for classical simulation capabilities, particularly in the context of sampling in the computational basis and computing Pauli expectation values. They highlight the potential for efficient classical simulations of many-body quantum systems and quantum circuits using CMPS representations.