Some embodiments in the present disclosure relate to an apparatus and methods for suppressing spontaneous emissions of two or more quantum emitters. The two or more quantum emitters are located in a plane. A reflector is located along an axis perpendicular to the plane. The reflector reflects an emission of a quantum emitter out of the two or more quantum emitters according to a boundary condition, wherein the boundary condition includes obtaining destructive interference of the reflected emissions with the emissions of the two or more quantum emitters.

Some embodiments in the present disclosure relate to an apparatus and methods for guiding spontaneous emissions of a quantum emitter in a first spatial direction. A reflector reflects an emission of the quantum emitter in a second spatial direction according to a boundary condition, wherein the boundary condition includes obtaining destructive interference of the reflected emission with the emission of the quantum emitter, and the reflector includes a portion adapted to guide an emission of the quantum emitter in the first spatial direction.

A composite confinement apparatus assembly is provided. The composite confinement apparatus assembly includes a quantum object confinement apparatus and a photonic platform. The confinement apparatus includes one or more electrical components and is fabricated on a confinement apparatus substrate. The photonic platform includes one or more photonic components that are hosted by a photonic platform substrate. The photonic platform substrate is mechanically coupled to the confinement apparatus substrate to form the composite confinement apparatus assembly.

Described herein are systems and methods for assembling electron spin and charge to possess one or more properties of a magnetic monopole. Example systems can include a laser configured to generate a light beam with a first spin and/or a first orbital angular momentum, and a surface including a coupling structure having a geometrical charge. When exposed to the light beam, the surface is configured to enable excitations of surface plasmon polariton field waves at metal-dielectric interfaces of the coupling structure to generate a plasmonic field. The surface can be configured to focus the plasmonic field to form a plasmonic vortex, in which plasmonic spin-orbit coupling between a total spin and a total orbital angular momentum forms a topological spin texture that is homotopic to that of a magnetic monopole.

An undulator comprises at least M permanent magnet periods arranged sequentially in a transmission direction of electron beams, each of the permanent magnet periods comprises four rows of permanent magnet structures, in which each row comprises N rows of permanent magnet groups, and each row of the permanent magnet groups comprises K permanent magnet units, wherein M, N and K are natural numbers greater than or equal to 1; the four rows of the permanent magnet structures are pairwise matched, then relatively disposed on both sides of the transmission direction of electron beams, and are capable of forming at least one composite magnetic fields by relative displacement, such that elliptically polarized light, circularly polarized light, or linearly polarized light with an arbitrary polarization angle of 0360 is generated when electron beams pass through the composite magnetic fields, and such that velocity directions of electrons are deviated from an axis direction of the undulator.

A device comprising a plurality of independent rotation gates, each rotation gate comprising a magnet configured to generate a magnetic field of predetermined strength at a qubit position for the respective rotation gate. The magnetic field is configured to generate a resonant frequency in qubits at the qubit position due to magnetically sensitive electronic states of the qubit. The device further comprises a first electromagnetic field source configured to generate an electromagnetic field at the resonant frequency for a predetermined period across the plurality of independent rotation gates. Each independent rotation gate comprises a controller configured to independently move the qubit at the respective independent rotation gate out of resonance at a predetermined time within the predetermined period.

A microwave photon control device includes a first qubit and a second qubit that are connected in parallel to a waveguide through which microwave photons propagate, and a direct coupling between the first qubit and the second qubit. An interval between the first qubit and the second qubit is (+n/2) times as long as a wavelength of microwave photons (where n is an integer equal to or larger than 0). A quantum entangled state is formed between the first qubit and the second qubit. The direct coupling cancels out a coupling via the waveguide between the first qubit and the second qubit. By a relaxation rate of the first qubit and the second qubit, and a phase of the quantum entangled state being controlled, the microwave photon control device operates while switching between a first operation mode, a second operation mode, and a third operation mode.

A device for controlling trapped ions includes a semiconductor substrate. The semiconductor substrate includes a first main surface and a second main surface opposite the first main surface. The substrate further includes a doped region adjacent the first main surface. An electrode of an ion trap is disposed over the doped region. An insulating layer is disposed between the electrode and the doped region. A contact region configured to be biased by an external potential is electrically connected to the doped region and has a doping concentration higher than a doping concentration of the doped region.

A flex ion trap interconnect for a quantum computing system is provided. The flex ion trap interconnect may be configured for operation in the temperature and pressure required by a vacuum chamber. The flex ion trap interconnect may include two or more connectors, which may be located at an end or middle of a flex ion trap interconnect and configured to connect to an ion trap of a quantum computing system to transmit electrical signals to and from the ion trap.

An optics-integrated confinement apparatus is provided. The optics-integrated confinement apparatus includes a first substrate, a plurality of electrical components formed on the first substrate, and an on-chip beam delivery system. The plurality of electrical components define a confinement apparatus configured/operable to confine one or more quantum objects. The on-chip beam delivery system includes a waveguide, a coupler, and an optical element. The coupler is configured to couple an optical beam out of the waveguide and toward the optical element. The optical element is configured to modify a polarization of the optical beam and direct the optical beam toward a target location defined by the optics-integrated confinement apparatus.