We changed our privacy policy. Read more.

Questions tagged [d-wave]

A quantum computing company, based in Burnaby, British Columbia, Canada, mostly known for their quantum annealing computers. An early rendition of these, D-Wave One, was the first commercially available quantum computer. (Wikipedia)

Filter by
Sorted by
Tagged with
1
vote
0answers
35 views

What should be the lowest energy of this graph isomorphism QUBO?

I am trying to study QUBO formulations of the graph isomorphism problem. I tried implementing the QUBO matrices given by the algorithms described in here. For the two input graphs therein, I am ...
2
votes
0answers
37 views

Sampling from a given Boltzmann distribution using D-Wave systems

For a project I'm working on, I want to use D-Wave systems to estimate the probabilities of a Boltzmann distribution given a QUBO (Hamiltonian), this being performed through sampling and the use of ...
1
vote
1answer
108 views

How is eigendecomposition of a Hamiltonian equivalent to finding the minimum of an energy function?

This question is in regards to Dwave's quantum computer which is tailored to solve QUBO problems using quantum annealing. QM tells us that the ground state of a quantum system is given by the ...
2
votes
1answer
69 views

From general Hamiltonian to Ising Hamiltonian

I would like to convert my qubit hamiltonian fom the HeH+ system that I have obtained using Qiskit to an Ising or QUBO model. I have seen multiples examples from QUBO to Qubit Hamiltonian but on the ...
1
vote
2answers
79 views

The Adiabatic Theorem - How to derive Schrödinger equation in the "s" variable

I'm studying Adiabatic Quantum computing from the book "Adiabatic Quantum Computation and Quantum Annealing: Theory and Practice" by Catherine C. McGeoch at D-Wave. The section THE ...
5
votes
2answers
268 views

Moore's law for quantum computers

Moore's law states that performance of classical computers doubles every two years (later revised to 18 months) and a price for computing resources halves during same time period. Currently, it seems ...
2
votes
0answers
22 views

Output of D-Wave LeapHybrid solver takes long to evaluate

we made the strange observation that the evaluation of the output in form of the dimod.SampleSet takes a long time to evaluate especially in comparison to the actual sampling step. Here is a minimal ...
2
votes
0answers
47 views

How to improve embedding process in D-Wave?

I am quite new to the quantum computing field. Currently, I am trying to solve a combinatorial optimization problem on a D-Wave system, which I successfully translated into QUBO form. I also managed ...
2
votes
1answer
93 views

From Qiskit QuadraticProgram to problem model accepted by d'wave ocean

Is there a way to convert QuadraticProgram (qiskit.optimization.problems.QuadraticProgram) to BQM used in D'wave ocean (e.g. <...
1
vote
1answer
36 views

What do the numbers in the Ising sampleset mean?

I am trying to create a portfolio optimization with the DWave Quantum Computer. I wrote some code trying to somehow reconstruct the following Ising model paper: Ai ...
5
votes
0answers
107 views

Inequality constraints on D'Wave (using PyQUBO)

Inequalities cannot be directly converted into a qubo form 0⩽ Expression ⩽ N We can introduce a slack variable and convert it to an equality problem: ⟹ Expression + s = N where: s ∈ Z, s ∈ [0,N] Since ...
3
votes
0answers
25 views

What is the state-of-the-art annealing device for solving Ising problems?

I understand that in addition to D-Wave's quantum annealer, there have been other unconventional (although non-quantum) Ising solvers like the one from Toshiba, Fujitsu, the Coherent Ising machine, ...
3
votes
1answer
37 views

How to decide bias in Hamiltonian Ising model?

I am trying to code finance portfolio optimisation problem into a quantum annealer, using the Hamiltonian Ising model. I am using the dwave module ...
2
votes
0answers
41 views

Why is it so important to have uniform chain lengths in a minor embedding?

Very brief background In quantum annealing, the discrete optimization problem we wish to solve (such as finding the minimum of $b_1b_2 - 3b_1 + 5b_3b_4$ for binary variables $b_i$) may have a ...
4
votes
2answers
77 views

What does it mean to have 2000 qubits and 6016 couplers?

From official D-Wave docs: The D-Wave 2000Q QPU has up to 2048 qubits and 6016 couplers. For example, I have the optimization problem defined as the QUBO problem. If I want to solve it on D-Wave,...
6
votes
2answers
125 views

What is the computational complexity of quantum annealing?

Quantum annealing can be thought of as a black box solver that can find approximate solutions to hard optimization problems. For example, D-Wave quantum annealers can approximately solve quadratic ...
2
votes
1answer
127 views

What is the problem in demonstrating quantum supremacy?

I am new to the quantum world and it's computing. But it accidentally hit in my mind that DWave built a quantum computer with 2000 qubits which can be use to simulate the whole observable universe or ...
7
votes
3answers
106 views

Is there quantum advantage to be had with a D-Wave computer in 2020?

I've seen a lot of excitement in the popular press about the computers made by D-Wave Systems, but when I dig deep the only practical things that I can figure out that one can do with the computer are ...
3
votes
0answers
48 views

D-WAVE QUBO Matrix Form

I am trying to write down this problem (friend/enemy graph) in a polynomial matrix form in order to understand quantum annealing better, but it seems like the problem should actually be split into ...
16
votes
1answer
3k views

Which subatomic particle does each company use in quantum computing?

Probably each company (Google, Amazon, Intel, IBM, Microsoft, D-Wave and so on) uses a mix of subatomic particles and technologies. I would like to know which particles/technologies are used by each ...
3
votes
2answers
343 views

What is an example of a simple QUBO problem?

I am digging into to the workings of the D-wave quantum annealing computers using this documentation. I find it very intuitive and well-explained, but their example of a "simple QUBO problem" does not ...
3
votes
0answers
47 views

What is the query complexity of the QUBO algorithm?

What is the complexity of the quantum unconstrained binary optimization (QUBO) algorithm in the number of queries to the quantum processor? To clarify, I'm asking about the complexity on quantum ...
3
votes
2answers
102 views

The commutation relation $[H_d, \sum_{i = 1}^n \sigma_i^z] = 0$ from the paper about the constrained quantum annealing (CQA)

A quote from the paper "Quantum annealing for constrained optimization" by I. Hen, F. M. Spedalieri: Let us now consider the driver Hamiltonian $$H_d = - \sum_{i=1}^n \left( \sigma_i^x \...
8
votes
2answers
404 views

What's a Qubit on D-Wave 2000Q?

From D-Wave flyer: The D-Wave 2000Q system has up to 2048 qubits and 5600 couplers. To reach this scale, it uses 128,000 Josephson junctions, which makes the D-Wave 2000Q QPU by far the most ...
3
votes
1answer
100 views
0
votes
1answer
236 views

How would D-Wave be used for complex optimization problems? [closed]

We are interested in solving an optimization problem, and specifically, the design of efficient yacht hulls. In designing an efficient yacht hull, one must consider water-hull resistance, wave ...
1
vote
0answers
51 views

How qubit phase is build in real hardware?

How qubit phase is build in real hardware? On IBM Quantum, D-Wave, etc?
1
vote
1answer
86 views

Quantum Annealing - Random results on big N

I implemented a solver for the Job Shop Problem, based on quantum annealing, on a D-Wave machine. I have a problem, that even though minimal energy solutions exist, they are only chosen once. I set ...
1
vote
1answer
93 views

Is it possible to use D-Wave systems for free?

IBM offers its platform IBM Q for free with certain constraints, such as available quantum processors and number of jobs running in parallel. I was wondering whether there is the same possibility on ...
2
votes
1answer
69 views

Quantum Annealing - Job Shop Problem

using this paper, I want to implement a solution for the Job Shop Problem on a D-Wave machine. One of the constraints mentioned in the paper, is $$ h_3(\bar{x}) = \sum_i \left(\sum_t x_{i,t}-1 \right)^...
1
vote
0answers
47 views

Suggestions for hybrid factoring algorithm on DWave and Qiskit

I was wondering if the multi-prime factoring problem can be solved in a hybrid approach using DWave (to factor) and Shor's algorithm (in Qiskit)? Please let me know your thoughts. Thanks!
9
votes
3answers
1k views

What is D-Wave's "Pegasus" architecture?

How is D-Wave's Pegasus architecture different from the Chimera architecture?
1
vote
1answer
119 views

Minimum Spanning Tree on D Wave Processor

I am attempting to implement a minimum spanning tree problem on the D wave quantum computing architecture. I have seen many graph problems implemented, such as a graph coloring example. There are also ...
1
vote
2answers
249 views

How to get samples in "bins" from D-Wave's dimod?

at 1, the following code example is available: ...
6
votes
1answer
227 views

Hardware wise, how does D-Wave achieve quantum annealing?

Quantum computers have shown a new way to compute old problems. D-Wave has a quantum annealer, and Wikipedia describes the D-Wave quantum computer and its use of quantum annealing properties. ...
6
votes
1answer
179 views

Do the latest D-Wave computers use Helium compounds for cooling?

Do the latest D-Wave machines use compounds of $\require{\mhchem}\ce{^{3}He}$ and $\ce{^{4}He}$ for cooling? If not, how does D-Wave approach cooling its plates low enough to achieve superconductivity?...
32
votes
3answers
3k views

How do you write a simple program for a D-Wave device?

I would like to know how a job for a D-Wave device is written in code and submitted to the device. In the answer it would be best to see a specific example of this for a simple problem. I guess that ...
43
votes
2answers
6k views

Is there proof that the D-wave (one) is a quantum computer and is effective?

I'm admittedly a novice in this field, but I have read that, while the D-wave (one) is an interesting device, there is some skepticism regarding it being 1) useful and 2) actually a 'quantum computer'....
7
votes
1answer
354 views

How can a D-Wave style Annealing QPU help sampling?

This question is a follow-up on this one, with the hope of getting more specific clues, and was motivated by this answer by user Rob. Also please note this posts that handle the topic of QA in much ...
3
votes
0answers
73 views

How to calculate the $r^{\text{th}}$ digit of $\sum ^{j−1}_{p=i}d^p_{\pm k}$ using PyQUBO?

I am going to implement "turn circuit encoding" method of Coarse-grained lattice protein folding on a quantum annealer(Babej, Ing & Fingerhuth; 2018) using PyQUBO to run on the DWave qbsolv ...
8
votes
2answers
742 views

How to explain in layman’s terms the significance of the difference of qubits of the D-Wave and IBM QX?

So, @AndrewO mentioned recently that he has had 'encounters' with people wondering why D-Wave has a lot more qubits than IBM. Of course, this comparison is faulty, since the IBM and D-Wave's machine ...
5
votes
1answer
920 views

D-Wave systems and IBM Q System One

What is the difference between the D-Wave systems and the newly-born IBM Q System One?
4
votes
2answers
121 views

Are there established best practices for designing Dwave embeddings?

Some of my larger annealer embeddings (~200 qubits) don't anneal down to the ground state while some of them do very easily. Are there established guidelines for designing annealer embeddings to ...
1
vote
0answers
29 views

What are techniques are used to esimate the spectral properties of annealer embedding hamiltonians?

Some information about the spectral properties of the hamiltonian of a given annealer emebedding is needed to determine a proper annealing schedule, correct? What are methods that are used to find ...
6
votes
1answer
537 views

What are XX, YY, YZ etc. couplings?

The D-wave quantum computer allows us to be able to minimize Ising models. In reading other questions and responses, particularly What would be the simplest addition that would make the D-Wave ...
22
votes
2answers
2k views

Why can't quantum annealing be described by a gate model?

This is a question I was inspired to ask based on this question, which notes that quantum annealing is an entirely different model for computation than the usual circuit model. I've heard this before, ...
11
votes
1answer
350 views

Does the D-Wave 2000Q satisfy DiVincenzo's criteria?

DiVincenzo's criteria for quantum computation are the following: A scalable physical system with well characterized qubits. The ability to initialize the state of the qubits to a simple fiducial ...
3
votes
2answers
200 views

Why D-Wave 2000Q requires such a low pressure?

On the D-Wave 2000Q website, it is stated that the processor environment is kept "in a high vacuum: pressure is 10 billion times lower than atmospheric pressure". Why the pressure has to be such low? ...
6
votes
0answers
124 views

What methods exist for cooling superconducting quantum computers? [duplicate]

Existing superconducting quantum computers need to be cooled near absolute zero. For example, some of D-Wave's machines are cooled to about $20 \ \mathrm {mK}$. Their design uses a dilution ...
2
votes
1answer
65 views

What is the "TRIAD" graph and where can I find more information about it?

I was looking up how to program for a D-Wave machine and I came across this image which says it's the "optimal hardware graph" for a D-Wave machine: Unfortunately the image seems to have come from ...