Me wrinting a minimalistic readme
This is a simple pulse library that is made to work together with the Keysight AWG. The main motivation for this library was to have a very easy and structured way to make waveforms. Also attention is given to performance for the construction of the waveform. The construction should always be faster than upload time (this was challaging since the upload goes via pcie + python ..). Performance critical parts are written in cython. Note that it is not the intention to support other AWG systems with this project (though the pulse builder should be genereric).
Features now include:
- Native support for virtual gates
- support for any pulse and sine waves (phase coherent atm)
- Sequencing
- delay in awg lines.
In progress:
- Fully multidimensionlisation of the segment object (with matrix operators)
- advanced (integrated) looping methods -- decorator approach + looping class. Support for calibarion arguments? -- this should be enegnneerd well.
- more base functions
- e.g. (IQ toolkit and IQ virtual channels) -- IF IQ is key for high performance (for IQ offset).
- Normal channels phase coherennt or not??
Todo list:
- Memory segmentation on the keysight awg. This will be needed if you want to upload during an experiment.
- Faster add function for block funtion (now performace issues if more than ~2000 elements in a sequence (not nice to call a lot)).
- support for memory segmentation for the keysight -- upload during experiment capelibility
Below are some basic commands that show how the library works.
Let's start by creating a pulse object. This is the main object that can be used to generate segments and sequences. The pulse object is best created in the station.
p = pulselib()One Could now define some segments for the experiment.
seg = p.mk_segment('INIT')
seg2 = p.mk_segment('Manip')
seg3 = p.mk_segment('Readout')These segments containers, where the segment for each gat can be accessed by calling seg.gate. Where gate is the name of the real/virtual gate you specified.
NOTE: A core idea of the package is that all the segments in the segment container (e.g. seg, seg2, seg3) have the same length.
To each segments you can add basic waveforms. Here you are free to add anything you want. Some examples follow (times are by default in ns).
seg.B0.add_pulse([[10,0],[10,5],[20,10],[20,0]]) # adds a linear ramp from 10 to 20 ns with amplitude of 5 to 10.
# B0 is the barrier 0 channel
seg.B0.add_block(40,70,2) # add a block pulse of 2V from 40 to 70 ns, to whaterver waveform is already there
seg.B0.wait(50) # just waits (e.g. you want to ake a segment 50 ns longer)
seg.B0.reset_time(). # resets time back to zero in segment. Al the commannds we run before will be put at a negative time.
seg.B0.add_block(0,10,2) # this pulse will be placed directly after the wait()Once pulses are added, you can define a sequence like:
SEQ = [['INIT', 1, 0], ['Manip', 1, 0], ['Readout', 1, 0] ]Where (e.g.) init is played once (1) and has a prescalor of 0 (see Keysight manual)
This sequence can be added to the pulse object and next be uploaded.
p.add_sequence('mysequence', SEQ)
p.start_sequence('mysequence')Virtual gates are also supported. This can simply be done by definig:
awg_virtual_channels = {'virtual_gates_names_virt' : ['vP1','vP2','vP3','vP4','vP5','vB0','vB1','vB2','vB3','vB4','vB5'],
'virtual_gates_names_real' : ['P1','P2','P3','P4','P5','B0','B1','B2','B3','B4','B5'],
'virtual_gate_matrix' : np.eye(11)}The virtual gates are simply accesible by calling seg.virtual_channel_name Note that thresolds are chosen automatically. Memory menagment is also taken care of for you :)
There is also a virtual gate the can be defined for IQ channnels. This takes automatically care of IQ math for you (makes it super easy to work with IF based schemes).
awg_IQ_channels = {'vIQ_channels' : ['IQ1','IQ2']
'rIQ_channels' [['I1','Q1']['I2','Q2']],
'LO_freq' :[qcodes_param/float]
}Some examples of commonly made pulses:
- 1D scan
seg = p.mk_segment('1D_scan')
#lets sweep the virtual plunger,
n_points = 100
swing = 1000 #mV
period = 1000 #ns
v_start =swing/2
step = swing/npoints
for i in range(n_points):
seg.vP1.add_block(i*period, (i+1)period, v_start + i*step)
#done.- 2D scan
seg = p.mk_segment('2D_scan')
#lets sweep the virtual plunger 1 versus virtual plunger 2,
n_points1 = 100
n_points2 = 100
swing1 = 1000 #mV
swing2 = 1000 #mV
period = 1000 #ns
period1 = period #ns
period2 = period*n_points1 #ns
v_start1 =swing1/2
step1 = swing1/npoints1
v_start1 =swing1/2
step1 = swing1/npoints1
for i in range(n_points1):
seg.vP1.add_block(i*period1, (i+1)period1, v_start1 + i*step1)
seg.repeat(n_points2)
for i in range(n_points2):
seg.vP1.add_block(i*period2, (i+1)period2, v_start2 + i*step2)
#done.- 2D FM scan
lets build on top of the perv sample. let att the modulation on the real plungers (1 and 2) and barrier (2).
seg.P1.add_sin(10e6, ...)
...
- Ramsey experiment (using loops)
seg = p.mk_segment('Ramsey')
# do pi/2 pulse
seg.IQ.add_sin(0,100e-9,freq = 2e9, amp = 10, phase = 0)
# wait -- use a loop object (has access to default numpy operators if it is numerical)
times = lp.linspace(5,20e3, 500, axis=0, name="time", unit="ns")
seg.IQ.wait(times)
# reset time
seg.IQ.reset_time()
# do pi/2 pulse
seg.IQ.add_sin(0,100e-9,freq = 2e9, amp = 10, phase = 0)One can see that here a call to a single loopobject it made. We will be sweeping from 50ns to 20us. This sweep axis is 0 (first axis). The default is always a new axis. You only need to explicitely specify it if you want to parameters to be coupled (e.g. swept on the same axis). The name is optional and can be used for plotting, same for the unit.
- Rabi experiment (power vs frequency of the pulse): Good example of a two dimensioal sweep
seg = p.mk_segment('RABI')
t0 = 0
t1 = 50
freq = lp.linspace(1e9,1.1e9, 500, axis= 0, name="frequency", unit="Hz")
amp = lp.linspace(5,20e3, 500, axis= 1, name="VoltageIQ", unit="a.u.")
phase = 0
seg.IQ.add_sin(t0,t1,freq, amp, phase)