TY - JOUR

T1 - On the sign problem in the Hirsch-Fye algorithm for impurity problems

AU - Yoo, Jaebeom

AU - Chandrasekharan, Shailesh

AU - Kaul, Ribhu K.

AU - Ullmo, Denis

AU - Baranger, Harold U.

PY - 2005/12/2

Y1 - 2005/12/2

N2 - We show that there is no fermion sign problem in the Hirsch and Fye algorithm for the single-impurity Anderson model. Beyond the particle-hole symmetric case for which a simple proof exists, this has been known only empirically. Here we prove the nonexistence of a sign problem for the general case by showing that each spin trace for a given Ising configuration is separately positive. We further use this insight to analyse under what conditions orbitally degenerate Anderson models or the two-impurity Anderson model develop a sign.

AB - We show that there is no fermion sign problem in the Hirsch and Fye algorithm for the single-impurity Anderson model. Beyond the particle-hole symmetric case for which a simple proof exists, this has been known only empirically. Here we prove the nonexistence of a sign problem for the general case by showing that each spin trace for a given Ising configuration is separately positive. We further use this insight to analyse under what conditions orbitally degenerate Anderson models or the two-impurity Anderson model develop a sign.

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U2 - 10.1088/0305-4470/38/48/004

DO - 10.1088/0305-4470/38/48/004

M3 - Article

AN - SCOPUS:27844549403

SN - 0305-4470

VL - 38

SP - 10307

EP - 10310

JO - Journal of Physics A: Mathematical and General

JF - Journal of Physics A: Mathematical and General

IS - 48

ER -