APPARATUS AND METHOD FOR ARBITRARY QUBIT ROTATION

• US 20190042973A1
• Filed: 09/27/2018
• Published: 02/07/2019
• Est. Priority Date: 09/27/2018
• Status: Active Application

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Zou, Xiang, Subramanian, Sushil
• Application Number:
  US16/145,062
• Publication Number:
  US 20190042973A1
• Time in Patent Office: Days
• CPC Class Codes: G06F 9/30 Arrangements for executing machine instructions, e.g. instruction decode for executing microinstructions G06F9/22
• CPC Class Codes: G06F 9/30007 to perform operations on data operands
• CPC Class Codes: G06F 9/30043 LOAD or STORE instructions; Clear instruction
• CPC Class Codes: G06F 9/30101 Special purpose registers
• CPC Class Codes: G06F 9/3016 Decoding the operand specifier, e.g. specifier format
• CPC Class Codes: G06F 9/30196 using decoder, e.g. decoder per instruction set, adaptable or programmable decoders
• CPC Class Codes: G06F 9/3802 Instruction prefetching
• CPC Class Codes: G06F 9/382 Pipelined decoding, e.g. using predecoding
• CPC Class Codes: G06F 9/3877 using a slave processor, e.g. coprocessor peripheral processor G06F13/12; vector processor G06F15/8053
• CPC Class Codes: G06N 10/00 Quantum computing, i.e. information processing based on quantum-mechanical phenomena
• CPC Class Codes: G06N 10/40 Physical realisations or architectures of quantum processors or components for manipulating qubits, e.g. qubit coupling or qubit control
• CPC Class Codes: G06N 20/00 Machine learning

Abstract

Apparatus and method for arbitrary qubit rotation. For example, one embodiment of a processor comprises: a decoder to decode a quantum rotation instruction specifying an arbitrary rotation value for performing a rotation of a quantum bit (qubit); a storage to store data for a plurality of waveform shapes/pulses; execution circuitry to perform the rotation of the qubit, the execution circuitry to combine a subset of the plurality of waveform shapes/pulses to approximate the arbitrary rotation value; and a classical-quantum (C-Q) interface coupled to the execution circuitry and comprising digital-to-analog circuitry to generate analog signals to rotate the qubit based on the approximation of the rotation value.

Claims

1. A processor comprising:

a decoder to decode a quantum rotation instruction specifying an arbitrary rotation value for performing a rotation of a quantum bit (qubit);

a storage to store data for a plurality of waveform shapes/pulses;

execution circuitry to perform the rotation of the qubit, the execution circuitry to combine a subset of the plurality of waveform shapes/pulses to approximate the arbitrary rotation value; and

a classical-quantum (C-Q) interface coupled to the execution circuitry and comprising digital-to-analog circuitry to generate analog signals to rotate the qubit based on the approximation of the rotation value.

2. The processor of claim 1 wherein the plurality of waveforms shapes/pulses comprise N waveforms shapes/pulses comprising values π

, π

/2, π

/4, π

/8, π

/16 . . . π

/2^N-1.

3. The processor of claim 1 wherein the execution circuitry is to perform a binary search operation to combine different subsets of the plurality of waveform shapes/pulses to identify a combination which results in an approximation closest to the arbitrary rotation value.

4. The processor of claim 1 further comprising:

a first source register to store a first value uniquely identifying the qubit, the quantum rotation instruction having a first operand to identify the first source register.

5. The processor of claim 4 further comprising:

a second source register to store the arbitrary rotation value, the quantum rotation instruction having a second operand to identify the second source register.

6. The processor of claim 4 wherein the quantum rotation instruction comprises an immediate to store the arbitrary rotation value.

7. The processor of claim 1 wherein the classical-quantum (C-Q) interface further comprises analog-to-digital circuitry to convert one or more analog measurements taken from one or more of the qubits to one or more digital values to be stored in a destination register within a register file.

8. The processor of claim 1 wherein the decoder comprises decode circuitry and/or microcode to generate a plurality of uops responsive to the quantum rotation instruction.

9. The processor of claim 8 further comprising:

an instruction fetch unit to fetch the quantum rotation instruction from a system memory or Level 1 (L1) instruction cache.

10. A method comprising:

decoding a quantum rotation instruction specifying an arbitrary rotation value for performing a rotation of a quantum bit (qubit);

performing the rotation of the qubit by combining a subset of a plurality of waveform shapes/pulses to generate an approximation of the arbitrary rotation value; and

generating analog signals to rotate the qubit based on the approximation of the rotation value.

11. The method of claim 10 wherein the plurality of waveforms shapes/pulses comprise N waveforms shapes/pulses comprising values π

, π

/2, π

/4, π

/8, π

/16 . . . π

/2^N-1.

12. The method of claim 10 combining different subsets of the plurality of waveform shapes/pulses comprises performing a binary search operation to identify a combination which results in an approximation closest to the arbitrary rotation value.

13. The method of claim 10 further comprising:

storing in a first source register a first value uniquely identifying the qubit, the quantum rotation instruction having a first operand to identify the first source register.

14. The method of claim 13 further comprising:

storing in a second source register the arbitrary rotation value, the quantum rotation instruction having a second operand to identify the second source register.

15. The method of claim 13 wherein the quantum rotation instruction comprises an immediate to store the arbitrary rotation value.

16. The method of claim 10 further comprising:

converting by analog-to-digital circuitry one or more analog measurements taken from one or more of the qubits to one or more digital values to be stored in a destination register within a register file.

17. The method of claim 10 wherein decoding comprises converting the quantum rotation instruction into a plurality of uops.

18. The method of claim 17 further comprising:

fetching the quantum rotation instruction from a system memory or Level 1 (L1) instruction cache.

19. A machine-readable medium having program code stored thereon which, when executed by a machine, causes the machine to perform the operations of:

decoding a quantum rotation instruction specifying an arbitrary rotation value for performing a rotation of a quantum bit (qubit);

performing the rotation of the qubit by combining a subset of a plurality of waveform shapes/pulses to generate an approximation of the arbitrary rotation value; and

generating analog signals to rotate the qubit based on the approximation of the rotation value.

20. The machine-readable medium of claim 19 wherein the plurality of waveforms shapes/pulses comprise N waveforms shapes/pulses comprising values π

, π

/2, π

/4, π

/8, π

/16 . . . π

/2^N-1.

21. The machine-readable medium of claim 19 combining different subsets of the plurality of waveform shapes/pulses comprises performing a binary search operation to identify a combination which results in an approximation closest to the arbitrary rotation value.

22. The machine-readable medium of claim 19 further comprising program code to cause the machine to perform the operations of:

storing in a first source register a first value uniquely identifying the qubit, the quantum rotation instruction having a first operand to identify the first source register.

23. The machine-readable medium of claim 22 further comprising program code to cause the machine to perform the operations of:

storing in a second source register the arbitrary rotation value, the quantum rotation instruction having a second operand to identify the second source register.

24. The machine-readable medium of claim 22 wherein the quantum rotation instruction comprises an immediate to store the arbitrary rotation value.

25. The machine-readable medium of claim 19 further comprising program code to cause the machine to perform the operations of:

converting by analog-to-digital circuitry one or more analog measurements taken from one or more of the qubits to one or more digital values to be stored in a destination register within a register file.

26. The machine-readable medium of claim 19 wherein decoding comprises converting the quantum rotation instruction into a plurality of uops.

27. The machine-readable medium of claim 26 further comprising program code to cause the machine to perform the operations of:

fetching the quantum rotation instruction from a system memory or Level 1 (L1) instruction cache.