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 -