# sf.ops¶

This module defines and implements the Python-embedded quantum programming language for continuous-variable (CV) quantum systems. The syntax is modeled after ProjectQ [33].

## Functions¶

 New([n]) Adds new subsystems to the quantum register.

## Classes¶

 Fourier gate. Position displacement gate. Momentum displacement gate. Rgate(theta) Rotation gate. Quadratic phase gate. Vgate(gamma) Cubic phase gate. Kgate(kappa) Kerr gate. CXgate([s]) Controlled addition or sum gate in the position basis. CZgate([s]) Controlled phase gate in the position basis. CKgate(kappa) Cross-Kerr gate. Dgate(r[, phi]) Phase space displacement gate. Sgate(r[, phi]) Phase space squeezing gate. BSgate([theta, phi]) Beamsplitter gate. MZgate(phi_in, phi_ex) Mach-Zehnder interferometer. S2gate(r[, phi]) Two-mode squeezing gate. Perform a loss channel operation on the specified mode. ThermalLossChannel(T, nbar) Perform a thermal loss channel operation on the specified mode. MSgate(r[, phi, r_anc, eta_anc, avg]) Phase space measurement-based squeezing gate. Perform an arbitrary multimode passive operation Prepare a mode in the vacuum state. Coherent([r, phi]) Prepare a mode in a coherent state. Squeezed([r, p]) Prepare a mode in a squeezed vacuum state. DisplacedSqueezed([r_d, phi_d, r_s, phi_s]) Prepare a mode in a displaced squeezed state. Fock([n]) Prepare a mode in a Fock basis state. Catstate([a, phi, p, representation, …]) Prepare a mode in a cat state. Thermal([n]) Prepare a mode in a thermal state. Ket(state) Prepare mode(s) using the given ket vector(s) in the Fock basis. DensityMatrix(state) Prepare mode(s) using the given density matrix in the Fock basis. Bosonic([weights, means, covs]) Prepare a mode as a linear combination of Gaussian functions in phase space. GKP([state, epsilon, ampl_cutoff, …]) Prepare a mode in a finite energy Gottesman-Kitaev-Preskill (GKP) state. MeasureFock([select, dark_counts]) Photon counting measurement: measures a set of modes in the Fock basis. MeasureHomodyne(phi[, select]) Performs a homodyne measurement, measures one quadrature of a mode. MeasureHeterodyne([select]) Performs a heterodyne measurement on a mode. MeasureThreshold([select]) Measures a set of modes with thresholded Fock-state measurements, i.e., measuring whether a mode contain zero or nonzero photons. Interferometer(U[, mesh, drop_identity, tol]) Apply a linear interferometer to the specified qumodes. BipartiteGraphEmbed(A[, …]) Embed a bipartite graph into an interferometer setup. GraphEmbed(A[, mean_photon_per_mode, …]) Embed a graph into an interferometer setup. GaussianTransform(S[, vacuum, tol]) Apply a Gaussian symplectic transformation to the specified qumodes. Gaussian(V[, r, decomp, tol]) Prepare the specified modes in a Gaussian state. All(op) Metaoperation for applying a single-mode operation to every mode in the register.

## Variables¶

 Del Deletes one or more existing modes. Vac Prepare a mode in the vacuum state. MeasureX Performs a homodyne measurement, measures one quadrature of a mode. MeasureP Performs a homodyne measurement, measures one quadrature of a mode. MeasureHD Performs a heterodyne measurement on a mode. Fourier Fourier gate.