Merge pull request #176 from BBN-Q/feature/CR-tomo

CR tomography and cancellation pulse
BBN-Q · Oct 1, 2018 · aebb371 · aebb371
2 parents a1e0249 + 996789c
commit aebb371
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Showing 2 changed files with 59 additions and 9 deletions.
diff --git a/QGL/BasicSequences/CR.py b/QGL/BasicSequences/CR.py
@@ -4,6 +4,7 @@
 from ..PulseSequencePlotter import plot_pulse_files
 from .helpers import create_cal_seqs, delay_descriptor, cal_descriptor
 import numpy as np
+from itertools import product
 
 def PiRabi(controlQ,
            targetQ,
@@ -56,7 +57,7 @@ def EchoCRLen(controlQ,
               amp=1,
               phase=0,
               calRepeats=2,
-              showPlot=False):
+              showPlot=False, canc_amp=0, canc_phase=np.pi/2):
     """
 	Variable length CX experiment, with echo pulse sandwiched between two CR opposite-phase pulses.
 
@@ -72,14 +73,14 @@ def EchoCRLen(controlQ,
 	showPlot : whether to plot (boolean)
 	"""
     seqs = [[Id(controlQ),
-             echoCR(controlQ, targetQ, length=l, phase=phase, amp=amp, riseFall=riseFall),
+             echoCR(controlQ, targetQ, length=l, phase=phase, amp=amp, riseFall=riseFall, canc_amp=canc_amp, canc_phase=canc_phase),
              Id(controlQ),
              MEAS(targetQ)*MEAS(controlQ)] for l in lengths] + \
            [[X(controlQ),
-             echoCR(controlQ, targetQ, length=l, phase= phase, amp=amp, riseFall=riseFall),
+             echoCR(controlQ, targetQ, length=l, phase= phase, amp=amp, riseFall=riseFall, canc_amp=canc_amp, canc_phase=canc_phase),
              X(controlQ),
              MEAS(targetQ)*MEAS(controlQ)] for l in lengths] + \
-           create_cal_seqs((targetQ,controlQ), calRepeats, measChans=(targetQ,controlQ))
+           create_cal_seqs((targetQ,controlQ), calRepeats, measChans=(targetQ, controlQ))
 
     metafile = compile_to_hardware(seqs, 'EchoCR/EchoCR',
         axis_descriptor=[
@@ -100,7 +101,9 @@ def EchoCRPhase(controlQ,
                 amp=1,
                 length=100e-9,
                 calRepeats=2,
-                showPlot=False):
+                showPlot=False,
+                canc_amp=0,
+                canc_phase=np.pi/2):
     """
 	Variable phase CX experiment, with echo pulse sandwiched between two CR opposite-phase pulses.
 
@@ -116,11 +119,11 @@ def EchoCRPhase(controlQ,
 	showPlot : whether to plot (boolean)
 	"""
     seqs = [[Id(controlQ),
-             echoCR(controlQ, targetQ, length=length, phase=ph, amp=amp, riseFall=riseFall),
+             echoCR(controlQ, targetQ, length=length, phase=ph, amp=amp, riseFall=riseFall, canc_amp=canc_amp, canc_phase=canc_phase),
              X90(targetQ)*Id(controlQ),
              MEAS(targetQ)*MEAS(controlQ)] for ph in phases] + \
            [[X(controlQ),
-             echoCR(controlQ, targetQ, length=length, phase= ph, amp=amp, riseFall = riseFall),
+             echoCR(controlQ, targetQ, length=length, phase= ph, amp=amp, riseFall = riseFall, canc_amp=canc_amp, canc_phase=canc_phase),
              X90(targetQ)*X(controlQ),
              MEAS(targetQ)*MEAS(controlQ)] for ph in phases] + \
              create_cal_seqs((targetQ,controlQ), calRepeats, measChans=(targetQ,controlQ))
@@ -192,3 +195,33 @@ def EchoCRAmp(controlQ,
         plot_pulse_files(metafile)
 
     return metafile
+
+def CRtomo_seq(controlQ, targetQ, lengths, ph, amp=0.8, riseFall=20e-9):
+    """
+    Variable length CX experiment, for Hamiltonian tomography.
+
+    Parameters
+    ----------
+    controlQ : logical channel for the control qubit (LogicalChannel)
+    targetQ: logical channel for the target qubit (LogicalChannel)
+    lengths : pulse lengths of the CR pulse to sweep over (iterable)
+    riseFall : rise/fall time of the CR pulse (s)
+    ph : phase of the CR pulse (rad)
+    """
+    CRchan = ChannelLibraries.EdgeFactory(controlQ, targetQ)
+    tomo_pulses = [Y90m, X90, Id]
+    seqs = [[Id(controlQ),
+         flat_top_gaussian(CRchan, amp=amp, riseFall=riseFall, length=l, phase=ph, label="CR"),
+         Id(controlQ)*tomo_pulse(targetQ),
+         MEAS(targetQ)] for l,tomo_pulse in product(lengths, tomo_pulses)] + \
+       [[X(controlQ),
+         flat_top_gaussian(CRchan, amp=amp, riseFall=riseFall, length=l, phase=ph, label="CR"),
+         X(controlQ)*tomo_pulse(targetQ),
+         MEAS(targetQ)] for l,tomo_pulse in product(lengths, tomo_pulses)] + \
+       create_cal_seqs((targetQ,), 2,)
+    metafile = compile_to_hardware(seqs, 'CR/CR',
+        axis_descriptor=[
+            delay_descriptor(np.concatenate((np.repeat(lengths,3), np.repeat(lengths,3)))),
+            cal_descriptor((targetQ,), 2)
+        ])
+    return metafile
diff --git a/QGL/PulsePrimitives.py b/QGL/PulsePrimitives.py
@@ -646,7 +646,7 @@ def echoCR(controlQ,
            phase=0,
            length=200e-9,
            riseFall=20e-9,
-           lastPi=True):
+           lastPi=True, canc_amp = 0.0, canc_phase=np.pi/2):
     """
     An echoed CR pulse.  Used for calibration of CR gate
     """
@@ -668,6 +668,19 @@ def echoCR(controlQ,
                              length=length,
                              phase=phase + np.pi,
                              label="echoCR_second_half")]
+    if canc_amp != 0:
+        seq[0]*=flat_top_gaussian(targetQ,
+                            amp=canc_amp,
+                            riseFall=riseFall,
+                            length=length,
+                            phase=canc_phase,
+                            label="cancCR_first_half")
+        seq[2]*=flat_top_gaussian(targetQ,
+                            amp=canc_amp,
+                            riseFall=riseFall,
+                            length=length,
+                            phase=canc_phase + np.pi,
+                            label="cancCR_second_half")
     if lastPi:
         seq += [X(controlQ)]
     return CompoundGate(seq)
@@ -679,12 +692,16 @@ def ZX90_CR(controlQ, targetQ, **kwargs):
     """
     CRchan = ChannelLibraries.EdgeFactory(controlQ, targetQ)
     params = overrideDefaults(CRchan, kwargs)
+    canc_amp = params['canc_amp'] if 'canc_amp' in params else 0
+    canc_phase = params['canc_phase'] if 'canc_phase' in params else 0
     return echoCR(controlQ,
                   targetQ,
                   amp=params['amp'],
                   phase=params['phase'],
                   length=params['length'],
-                  riseFall=params['riseFall'])
+                  riseFall=params['riseFall'],
+                  canc_phase=canc_phase,
+                  canc_amp=canc_amp)
 
 
 def CNOT_CR(controlQ, targetQ, **kwargs):