From f23ed914c05fd48931ab7673ad97247580d11d59 Mon Sep 17 00:00:00 2001
From: quaeritis <quaeritis@rebellare.de>
Date: Wed, 20 Jan 2021 12:03:26 +0100
Subject: [PATCH] add singns argument for add_peierls_phase
---
kwant/builder.py | 25 ++++++++++++++++++++-----
1 file changed, 20 insertions(+), 5 deletions(-)
diff --git a/kwant/builder.py b/kwant/builder.py
index 3ffdf099..f65a8e08 100644
--- a/kwant/builder.py
+++ b/kwant/builder.py
@@ -1528,13 +1528,24 @@ class Builder:
_require_system
-def _add_peierls_phase(syst, peierls_parameter):
+def _add_peierls_phase(syst, peierls_parameter, signs):
+ def phi_matrix(phi, signs):
+ phase_factors = []
+ for sign in signs:
+ if sign == -1:
+ phase_factors.append(phi.conjugate())
+ elif sign == 1:
+ phase_factors.append(phi)
+ return np.diag(phase_factors)
@memoize
def wrap_hopping(hop):
def f(*args):
a, b, *args, phi = args
- return hop(a, b, *args) * phi(a, b)
+ if signs is not None:
+ return np.dot(hop(a, b, *args), phi_matrix(phi(a, b), signs))
+ else:
+ return hop(a, b, *args) * phi(a, b)
params = ('_site0', '_site1')
if callable(hop):
@@ -1550,7 +1561,10 @@ def _add_peierls_phase(syst, peierls_parameter):
const_hoppings = {}
def const_hopping(a, b, phi):
- return const_hoppings[a, b] * phi(a, b)
+ if signs is not None:
+ return np.dot(hop(a, b, *args), phi_matrix(phi(a, b), signs))
+ else:
+ return hop(a, b, *args) * phi(a, b)
# fix the signature
params = ('_site0', '_site1', peierls_parameter)
@@ -1571,6 +1585,7 @@ def _add_peierls_phase(syst, peierls_parameter):
_add_peierls_phase(
lead.builder,
peierls_parameter + '_lead{}'.format(i),
+ signs
),
lead.interface,
lead.padding,
@@ -1590,7 +1605,7 @@ def _add_peierls_phase(syst, peierls_parameter):
return ret
-def add_peierls_phase(syst, peierls_parameter='phi', fix_gauge=True):
+def add_peierls_phase(syst, peierls_parameter='phi', fix_gauge=True, signs=None):
"""Add a Peierls phase parameter to a Builder.
Parameters
@@ -1690,7 +1705,7 @@ def add_peierls_phase(syst, peierls_parameter='phi', fix_gauge=True):
raise TypeError("'add_peierls_phase' does not work with "
"vectorized Builders")
- ret = _add_peierls_phase(syst, peierls_parameter).finalized()
+ ret = _add_peierls_phase(syst, peierls_parameter, signs).finalized()
if fix_gauge:
return ret, wrap_gauge(magnetic_gauge(ret))
--
GitLab