Source code for pyepr.hardware.xepr_experiments

import importlib
import time
import numpy as np
import re
import pyepr.tools as tools
from scipy.optimize import minimize_scalar, curve_fit
from pyepr.hardware import XeprAPILink
from deerlab import correctphase
from numpy.polynomial import Polynomial

[docs] MODULE_DIR = importlib.util.find_spec('pyepr').submodule_search_locations[0]
# =============================================================================
[docs] def get_nutations(api, nu, field, step, ELDOR: bool = True, nx: int = 128): min_freq = nu[0] max_freq = nu[1] freq_table = np.arange(min_freq, max_freq, step) n = len(freq_table) if len(field) == 2: input_freq = field[0] input_field = field[1] start_field = input_field * min_freq / input_freq elif len(field) == 1: start_field = field field_table = freq_table * start_field/min_freq # go to start field / freq api.set_field(field_table[0], hold=True) api.set_freq(freq_table[0]) if ELDOR: api.set_ELDOR_freq(freq_table[0]) nut_data = np.zeros((n, nx+1), dtype=np.complex64) tools.progress_bar_frac(0, n) for i in range(0, n): api.set_field(field_table[i], hold=True) api.set_freq(freq_table[i]) if ELDOR: api.set_ELDOR_freq(freq_table[i]) api.run_exp() while api.is_exp_running(): time.sleep(0.5) dataset = api.acquire_dataset() nut_data[i, 0] = api.get_counterfreq() nut_data[i, 1:] = dataset.data t = dataset.axes tools.progress_bar_frac(i+1, n) return t, nut_data
# =============================================================================
[docs] def CP_run( api, d0, num_pulses=3, ps_length=16, sweeps=4, dt=100, num_points=256, srt = 6e6): if num_pulses == 2: run_general( api, ["/PulseSpel/HUKA_DEER_AWG"], ["5p DEER relax", "DEER run AWG -+<x>"], {"PhaseCycle": True}, {"p0": ps_length, "p1": ps_length, "h": 10, "n": sweeps, "d30": dt, "d0": d0, "dim10": num_points, "srt": srt}, False) else: raise ValueError("Only CP2 is currently implemented")
# =============================================================================
[docs] def DEER5p_run( api, ps_length, d0, tau2, sweeps=4, deadtime=80, dt=16, num_points=0, srt=6e6): if num_points == 0: num_points = np.floor((tau2 + tau2 - deadtime)/dt) run_general( api, ["/PulseSpel/HUKA_DEER_AWG"], ["5p DEER", "DEER run AWG -+<x>"], {"PhaseCycle": True, "ReplaceMode": False}, {"p0": ps_length, "p1": ps_length, "h": 20, "n": sweeps, "d2": tau2, "d11": 200, "d3": deadtime, "d30": dt, "d0": d0, "dim8": num_points, "srt": srt}, run=False)
# ============================================================================= class DEER: def __init__(self, api, d0, det_frq, pump_frq, srt=6e6) -> None: self.api = api self.d0 = d0 self.det_frq = det_frq self.pump_frq = pump_frq self.mpfu = True self.hybrid = False self.awg = False self.srt = srt pass def run_5p( self, tau1: float, tau2: float, dt: float = 16, deadtime: float = 80, num_points: int = 0, scans: int = 200) -> None: ps_length = 32 if num_points == 0: num_points = np.floor((tau2 + tau2 - deadtime)/dt) # Add some selection based on AWG / HYBRID/ MPFU if self.awg: print("Bruker AWG are not yet supported") elif self.hybrid: ps_file = "/PulseSpel/HUKA_DEER_AWG" ps_exp = "5pDEER" ps_pc = "DEER run" elif self.mpfu: ps_file = "/PulseSpel/aD_DEER_MPFU" ps_exp = "5p DEER" ps_pc = "DEER run AWG -+<x>" run_general( self.api, [ps_file], [ps_exp, ps_pc], {"PhaseCycle": True, "ReplaceMode": False}, {"p0": ps_length, "p1": ps_length, "h": 20, "n": scans, "d2": tau2, "d11": 200, "d3": deadtime, "d30": dt, "d0": self.d0, "dim8": num_points, "srt": self.srt}, run=True) pass def run_4p( self, tau1: float, tau2: float, dt: float = 16, deadtime: float = 80, num_points: int = 0, scans: int = 200) -> None: ps_length = 32 if num_points == 0: num_points = np.floor((tau2 + tau2 - deadtime)/dt) # Add some selection based on AWG / HYBRID/ MPFU if self.awg: print("Bruker AWG are not yet supported") elif self.hybrid: ps_file = "/PulseSpel/HUKA_DEER_AWG" ps_exp = "4pDEER" ps_pc = "DEER run" elif self.mpfu: ps_file = "/PulseSpel/aD_DEER_MPFU" ps_exp = "4-DEER AWG" ps_pc = "DEER run AWG -+<x>" run_general( self.api, [ps_file], [ps_exp, ps_pc], {"PhaseCycle": True, "ReplaceMode": False}, {"p0": ps_length, "p1": ps_length, "h": 20, "n": scans, "d2": tau2, "d11": 200, "d3": deadtime, "d30": dt, "d0": self.d0, "dim8": num_points, "srt": self.srt}, run=True) pass def run_CP(self, tau: int, dt: int = 50, num_points: int = 200, scans: int = 1) -> None: ps_length = 32 if self.awg: print("Bruker AWG are not yet supported") elif self.hybrid or self.mpfu: ps_file = "/PulseSpel/HUKA_DEER_AWG" ps_exp = "4pDEER" ps_pc = "DEER run" run_general( self.api, [ps_file], [ps_exp, ps_pc], {"PhaseCycle": True, "ReplaceMode": False}, {"p0": ps_length, "p1": ps_length, "h": 20, "n": scans, "d1": tau, "d30": dt, "d0": self.d0, "dim8": num_points, "srt": self.srt}, run=True) pass # ============================================================================= class MPFUtune: """ Tuning MPFU channels for optimal attenuation and phase """ def __init__(self, api, echo="Hahn", ps_length=16, d0=680, srt=6e6) -> None: """ Parameters ---------- api : _type_ The spectrometr API object echo : str, optional The echo type. Options = ['Hahn","Refocused"], by default "Hahn" ps_length : int, optional The length of the pi/2 pulse, by default 16 d0 : int, optional The approximate position of d0, this should be lower than ideal, by default 680 """ self.api = api self.hardware_wait = 5 # seconds self.ps_length = ps_length self.d0 = d0 self.srt = srt if echo == "Hahn": self._setup_echo("Hahn Echo", tau1=400) elif echo == "Refocused": self._setup_echo("Refocused Echo", tau1=200, tau2=400) else: raise ValueError( "Only Hahn and Refocused echo's are currently supported") pass def _setup_echo(self, echo, tau1=400, tau2=400): PulseSpel_file = "/PulseSpel/phase_set" run_general(self.api, [PulseSpel_file], [echo, "BrXPhase"], {"PhaseCycle": False}, {"p0": self.ps_length*2, "p1": self.ps_length, "h": 20, "n": 1, "d0": self.d0, "d1": tau1, "d2": tau2, "pg": 128, "srt": self.srt}, run=False ) def tune_phase( self, channel: str, target: str, tol=0.1, maxiter=30) -> float: """Tunes the phase of a given channel to a given target using the standard scipy optimisation scripts. Parameters ---------- channel : str The chosen MPFU channel. Options: ['+<x>', '-<x>', '+<y>', '-<y>'] target : str The target echo position, this can either be maximising (+) or minimising (-) either the real (R) or imaginary (I) of the echo. Options: ['R+', 'R-', 'I+', 'I-'] tol : float, optional The tolerance in phase parameter, by default 0.1 maxiter : int, optional The maximum number of iterations in the optimisation, by default 30 Returns ------- float The optimal value of the phase parameter """ channel_opts = ['+<x>', '-<x>', '+<y>', '-<y>'] phase_opts = ['R+', 'R-', 'I+', 'I-'] if channel not in channel_opts: raise ValueError(f'Channel must be one of: {channel_opts}') if target not in phase_opts: raise ValueError(f'Phase target must be one of: {phase_opts}') if channel == '+<x>': phase_channel = 'BrXPhase' elif channel == '-<x>': phase_channel = 'BrMinXPhase' elif channel == '+<y>': phase_channel = 'BrYPhase' elif channel == '-<y>': phase_channel = 'BrMinYPhase' if target == 'R+': test_fun = lambda x: -1 * np.real(x) elif target == 'R-': test_fun = lambda x: 1 * np.real(x) elif target == 'I+': test_fun = lambda x: -1 * np.imag(x) elif target == 'I-': test_fun = lambda x: 1 * np.imag(x) lb = 0.0 ub = 100.0 def objective(x, *args): # x = x[0] self.api.hidden[phase_channel].value = x # Set phase to value time.sleep(self.hardware_wait) self.api.run_exp() while self.api.is_exp_running(): time.sleep(1) data = self.api.acquire_scan() v = data.data val = test_fun(np.sum(v)) print(f'Phase Setting = {x:.1f} \t Echo Amplitude = {-1*val:.2f}') return val output = minimize_scalar( objective, method='bounded', bounds=[lb, ub], options={'xatol': tol, 'maxiter': maxiter}) result = output.x print(f"Optimal Phase Setting for {phase_channel} is: {result:.1f}") self.api.hidden[phase_channel].value = result return result def tune_power( self, channel: str, tol=0.1, maxiter=30, bounds: list[float] = [0, 100]) -> float: """Tunes the attenuator of a given channel to a given target using the standard scipy optimisation scripts. Parameters ---------- channel : str The chosen MPFU channel. Options: ['+<x>', '-<x>', '+<y>', '-<y>'] tol : float, optional The tolerance in attenuator parameter, by default 0.1 maxiter : int, optional The maximum number of iterations in the optimisation, by default 30 Returns ------- float The optimal value of the attenuator parameter """ channel_opts = ['+<x>', '-<x>', '+<y>', '-<y>'] if channel not in channel_opts: raise ValueError(f'Channel must be one of: {channel_opts}') if channel == '+<x>': atten_channel = 'BrXAmp' elif channel == '-<x>': atten_channel = 'BrMinXAmp' elif channel == '+<y>': atten_channel = 'BrYAmp' elif channel == '-<y>': atten_channel = 'BrMinYAmp' lb = bounds[0] ub = bounds[1] def objective(x, *args): self.api.hidden[atten_channel].value = x # Set phase to value time.sleep(self.hardware_wait) self.api.run_exp() while self.api.is_exp_running(): time.sleep(1) data = self.api.acquire_scan() v = data.data val = -1 * np.sum(np.abs(v)) print(f'Power Setting = {x:.1f} \t Echo Amplitude = {-1*val:.2f}') return val output = minimize_scalar( objective, method='bounded', bounds=[lb, ub], options={'xatol': tol, 'maxiter': maxiter}) result = output.x print(f"Optimal Power Setting for {atten_channel} is: {result:.1f}") self.api.hidden[atten_channel].value = result return result def tune(self, channels: dict, tol: float = 0.1, bounds=[0, 100]) -> None: """Tunes both the power and attenuation for a collection of channels. Parameters ---------- channels : dict A dictionary of MPFU channels to be tunned and the associated phase target.\\ Channel options = ['+<x>', '-<x>', '+<y>', '-<y>']\\ Phase target options = ['R+', 'R-', 'I+', 'I-']\\ E.g. {'+<x>': 'R+','-<x>': 'R-'} tol : float, optional The tolerance for all optimisations, by default 0.1 """ for channel in channels: if channel == '+<x>': phase_cycle = 'BrXPhase' elif channel == '-<x>': phase_cycle = 'BrMinXPhase' elif channel == '+<y>': phase_cycle = 'BrYPhase' elif channel == '-<y>': phase_cycle = 'BrMinYPhase' self.api.set_PulseSpel_phase_cycling(phase_cycle) print(f"Tuning channel: {channel}") self.tune_power(channel, tol=tol, bounds=bounds) self.tune_phase(channel, channels[channel], tol=tol) def calc_d0(self): initial_d0 = 500 PulseSpel_file = "/PulseSpel/phase_set" run_general( self.api, [PulseSpel_file], ['Hahn Echo Trans', "BrXPhase"], {"PhaseCycle": False}, {"p0": self.ps_length*2, "p1": self.ps_length, "h": 20, "n": 1, "d1": 400, "d0": initial_d0} ) while self.api.is_exp_running(): time.sleep(1) data = self.api.acquire_scan() max_pos = np.argmax(np.abs(data.data)) max_time = data.axes[max_pos] d0 = initial_d0 + max_time return d0 # ============================================================================= class ELDORtune: def __init__(self, api: XeprAPILink, d0=700, ps_length=16, srt=6e6) -> None: """ Tuning incoherent ELDOR channel for optimal power using nutation experiments Parameters ---------- api : XeprAPILink The spectrometer API object d0 : int, optional The approximate position of d0, this should be lower than ideal, by default 700 ps_length : int, optional The length of the pi/2 pulse, by default 16 """ self.api = api self.d0 = d0 self.ps_length = ps_length self.hardware_wait = 5 self.srt = srt pass def _setup_exp(self, tau1=400, tau2=400): PulseSpel_file = "/PulseSpel/param_opt" run_general(self.api, [PulseSpel_file], ["nutation", "ELDOR nut"], {"PhaseCycle": True}, {"p0": self.ps_length*2, "p1": self.ps_length, "h": 20, "n": 1, "d0": self.d0, "d1": tau1, "d2": tau2, "pg": 128, "dim7": 32, "srt": self.srt}, run=False ) def _get_exp(self): self.api.run_exp() data = self.acquire_scan() return data def find_min(self, dataset): data = correctphase(dataset.data) data /= data.max() time = dataset.axes def test_fun(x, A, B, freq, phase, decay): return A*np.sin(x*2*np.pi*freq + phase)*np.exp(-1*x*decay) + B bounds = ( [-1.5, -1, 0, -np.pi, 0], [1.5, 1.5, 1, np.pi, 10] ) p0 = [0.5, 0.6, 0.04, 1.4, 0.03] popt, pcov = curve_fit( test_fun, time, data, p0=p0, bounds=bounds) return 1/(2*popt[2]) def tune(self, target: int): lb = 0 ub = 30 tol = 2 maxiter = 10 def objective(x, *args): self.api.set_attenuator("ELDOR", x) time.sleep(self.hardware_wait) self.api.run_exp() while self.api.is_exp_running(): time.sleep(1) dataset = self.api.acquire_scan() min = self.find_min(dataset) print(f'Atten Setting = {x:.1f} \t pi pulse time = {min:.1f} ns') return abs(min-args[0]) output = minimize_scalar( objective, method='bounded', bounds=[lb, ub], options={'xatol': tol, 'maxiter': maxiter}, args=target) result = output.x print(f"Optimal ELDOR atten is: {result:.1f}") self.api.set_attenuator("ELDOR", result) return result # ============================================================================= class PulseProfile: def __init__(self, api: XeprAPILink, d0=700, ps_length=16, srt=4e6) -> None: """ Tuning incoherent ELDOR channel for optimal power using nutation experiments Parameters ---------- api : XeprAPILink The spectrometr API object d0 : int, optional The approximate position of d0, this should be lower than ideal, by default 700 ps_length : int, optional The length of the pi/2 pulse, by default 16 """ self.api = api self.d0 = d0 self.ps_length = ps_length self.hardware_wait = 5 self.srt = srt pass def _setup_exp(self, tau=400): r""" Setup the pulse profile experiment. Parameters ---------- tau : int, optional The seperation between :math:'\pi/2' and :math:'pi' in the Hahn echo, by default 400 """ PulseSpel_file = "/PulseSpel/param_opt" run_general(self.api, [PulseSpel_file], ["PulseProfile ELDOR", "ELDOR nut"], {"PhaseCycle": True}, {"p0": self.ps_length*2, "p1": self.ps_length, "h": 20, "n": 1, "d0": self.d0, "d1": tau, "pg": 128, "dim8": 10, "srt": self.srt}, run=False ) def _freq_sweep(self, nu: list, step: float, gyro: float): """ Run the frequency sweep for a pulse profile. Parameters ---------- nu : list A list detailing the starting and ending frequency, [nu_init, nu_final] step : float The frequency step, given in GHz gyro : float The gyromagnetic ratio in G/GHz. Returns ------- _type_ _description_ """ min_freq = nu[0] max_freq = nu[1] freq_table = np.arange(min_freq, max_freq, step) n = len(freq_table) PP_x: np.ndarray = np.zeros(n, dtype=np.float32) PP: np.ndarray = np.zeros(n, dtype=np.complex128) # go to start field / freq self.api.set_freq(freq_table[0]) self.api.set_field(self.api.get_counterfreq()/gyro, hold=True) tools.progress_bar_frac(0, n) for i in range(0, n): self.api.set_freq(freq_table[i]) self.api.set_field(self.api.get_counterfreq()/gyro, hold=True) self.api.run_exp() while self.api.is_exp_running(): time.sleep(0.5) dataset = self.api.acquire_dataset() PP_x[i] = self.api.get_counterfreq() PP[i] = np.mean(dataset.data) tools.progress_bar_frac(i+1, n) return PP_x, PP # =============================================================================
[docs] def CalibrateFreq(api: XeprAPILink, num_points: int = 50, deg: int = 5): """Generate the polynomial parameters for converting from frequency (in GHz) to Xepr gunn diode stepper value. 0-4095. Parameters ---------- api : XeprAPILink The API for the spectrometer num_points : int, optional The number of points to be measured, by default 50 deg : int, optional The degree of polynomial fit, by default 5 """ positions = np.linspace(0, 4095, num_points, endpoint=True) array = np.zeros((2, positions)) for i, val in enumerate(positions): array[0, i] = val api.hidden['Frequency'] = val time.sleep(0.5) array[1, i] = api.get_counterfreq() pfit = Polynomial.fit(array[1, :], array[0, :], deg) return pfit.coef