A method for transmitting time information and quantum states on an optical medium is disclosed. The method includes transmitting information comprising a timing information and quantum states over a single wavelength on an optical medium. The method also includes receiving each transmitted information sequentially in the corresponding plurality of time slots at a receiver. The method also includes comparing each timing information received in the corresponding plurality of timeslots with timing information of a preceding hold over time slot of the plurality of time slots. The method also includes determining a time drift encountered at the receiver based on a compared result. The method also includes synchronising phase and frequency of the plurality of transmitted packets of the information based on minimization of determined time drift.

A method for transmitting time information and quantum states on an optical medium is disclosed. The method includes transmitting information comprising a timing information and quantum states over a single wavelength on an optical medium. The method also includes receiving each transmitted information sequentially in the corresponding plurality of time slots at a receiver. The method also includes comparing each timing information received in the corresponding plurality of timeslots with timing information of a preceding hold over time slot of the plurality of time slots. The method also includes determining a time drift encountered at the receiver based on a compared result. The method also includes synchronising phase and frequency of the plurality of transmitted packets of the information based on minimization of determined time drift.

A pair of acousto-optic deflectors (AODs) is used to steer a pair of laser beams to address individual atoms of an array of atoms so that the beams can conditionally induce a 2-photon transition between the atom's quantum energy levels. The first beam is deflected into a +1 diffraction order, resulting in an AOD output beam with a frequency greater than that of the respective AOD input beam. The second beam is deflected into a −1 diffraction order so that the AOD output beam has a frequency less than that of the respective AOD input beam. The equal and opposite frequency changes compensate it other so that the sum of the output frequencies remains resonant with the transition of interest. Thus, AODs can be used to steer laser beams to address individual atoms of an atom array.

A pair of acousto-optic deflectors (AODs) is used to steer a pair of laser beams to address individual atoms of an array of atoms so that the beams can conditionally induce a 2-photon transition between the atom's quantum energy levels. The first beam is deflected into a +1 diffraction order, resulting in an AOD output beam with a frequency greater than that of the respective AOD input beam. The second beam is deflected into a −1 diffraction order so that the AOD output beam has a frequency less than that of the respective AOD input beam. The equal and opposite frequency changes compensate it other so that the sum of the output frequencies remains resonant with the transition of interest. Thus, AODs can be used to steer laser beams to address individual atoms of an atom array.

A wireless system may include a central processor and an access point. The central processor may generate an optical signal on an optical fiber. The optical signal may include an optical local oscillator (LO) signal and one or more carriers. The central processor may modulate different combinations of transverse optical modes, orbital angular momentum, polarization, and/or carrier frequency of the optical signal to concurrently convey respective wireless data streams. The orthogonality of the transverse optical modes, orbital angular momentum, polarization, and carrier frequency may allow many wireless data streams to be modulated onto the optical signal and concurrently transmitted and propagated on the optical fiber independent of each other for transmission to one or more external devices.

The present invention relates to a quantum key distribution method 2000 for distributing a secret key over a quantum communication channel between a transmitter and a receiver, the method comprising the steps of: synchronizing S2100 a clock between the transmitter and the receiver, distributing S2200 the secret key from the transmitter to the receiver, wherein the synchronizing step S2100 comprises: a first transmitting step S2120 for transmitting a N-th bit of the clock from the transmitter to the receiver, a second transmitting step S2130 for transmitting acknowledgement of reception of the N-th bit from the receiver to the transmitter, a first checking step S2140 for checking if the N-th bit is a most significant bit of the clock, and an incrementing step S2150 for incrementing the value of N if the first checking step S2140 indicates that the N-th bit is not the most significant bit of the clock.

The present invention relates to a quantum key distribution method 2000 for distributing a secret key over a quantum communication channel between a transmitter and a receiver, the method comprising the steps of: synchronizing S2100 a clock between the transmitter and the receiver, distributing S2200 the secret key from the transmitter to the receiver, wherein the synchronizing step S2100 comprises: a first transmitting step S2120 for transmitting a N-th bit of the clock from the transmitter to the receiver, a second transmitting step S2130 for transmitting acknowledgement of reception of the N-th bit from the receiver to the transmitter, a first checking step S2140 for checking if the N-th bit is a most significant bit of the clock, and an incrementing step S2150 for incrementing the value of N if the first checking step S2140 indicates that the N-th bit is not the most significant bit of the clock.

A method for quantum communication between at least three receivers includes: i) generating an entangled photon pair in a source (2) with a signal photon in a signal wavelength range and an idler photon in an idler wavelength range, ii) assigning the signal and idler photons to the quantum channels (4) on the basis of their wavelength; iii) transmitting the photon pair to the receivers (3) via the quantum channels (4); iv) detecting the photon pair at the receivers (3).

The photons generated in step i) are generated in a signal wavelength range and an idler wavelength range that are spectrally separated from one another, and, in step ii), the photons are assigned to the quantum channels (4) such that, in step iii), only signal photons are transmitted to a first receiver (31) for the communication with all other receivers (3), and, in step iii), only idler photons are transmitted to a second receiver (32) for the communication with all other receivers (3), and, in step iii), both signal photons and idler photons are transmitted to the further receivers (33) for the communication with all other receivers (3), and all receivers (3) are connected to the source (2) via in each case one quantum channel (4).

A method for quantum communication between at least three receivers includes: i) generating an entangled photon pair in a source (2) with a signal photon in a signal wavelength range and an idler photon in an idler wavelength range, ii) assigning the signal and idler photons to the quantum channels (4) on the basis of their wavelength; iii) transmitting the photon pair to the receivers (3) via the quantum channels (4); iv) detecting the photon pair at the receivers (3).

The photons generated in step i) are generated in a signal wavelength range and an idler wavelength range that are spectrally separated from one another, and, in step ii), the photons are assigned to the quantum channels (4) such that, in step iii), only signal photons are transmitted to a first receiver (31) for the communication with all other receivers (3), and, in step iii), only idler photons are transmitted to a second receiver (32) for the communication with all other receivers (3), and, in step iii), both signal photons and idler photons are transmitted to the further receivers (33) for the communication with all other receivers (3), and all receivers (3) are connected to the source (2) via in each case one quantum channel (4).

Embodiments disclosed herein include electronic packages and methods of forming such electronic packages. In an embodiment, an electronic package comprises a first layer, where the first layer comprises glass. In an embodiment, a second layer is over the first layer, where the second layer comprises a mold material. In an embodiment, a first photonics integrated circuit (PIC) is within the second layer. In an embodiment, a second PIC is within the second layer, and a waveguide is in the first layer. In an embodiment, the waveguide optically couples the first PIC to the second PIC.