All Questions
Tagged with ibm-q-experience experimental-realization
24 questions
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0
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In qubit phase tracking, does the phase $\delta$ have to be synchronized to the Larmor precession?
In many textbooks (e.g. LaPierre 2021 or Byrd 2022), when dealing with the physical implementation of quantum gates in spin qubits, Larmor precession is usually introduced first as a way to rotate the ...
- 21
7
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1
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287
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Publicly available samples for quantum circuits and/or simulators
With Yosi Rinott and Tomer Shoham we studied various statistical aspects of samples coming from NISQ computers.
My question is about available data consisting of samples from NISQ computers
We would ...
- 201
7
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3
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3k
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How are IBM's 127 qubits more potent than the 5760 qubits D-Wave - Advantage_system6.1?
Hi I'm a newbie in quantum computing recently I had a look at the AWS braket and I've seen they had a machine called D-Wave - Advantage_system6.1 that has 5760 qubits but when I googled the highest ...
- 193
3
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2
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793
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'Internal error. Error code 9999' when running job on IBMQ
I'm trying to run a series of circuits in a job and I keep getting this error message which I haven't been able to find the meaning of anywhere in qiskit's documentation, online, etc. The job appears ...
6
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1
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116
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Do individual qubits on IBM quantum processors share the same control unit?
I want to investigate the maximum possible parallelism of quantum operations on a specific IBM device (such as the latest heavy-hex architecture), which requires a basic knowledge of their control ...
- 71
1
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1
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In the job tab, no histogram appears
(Newbie here) Accessing IBM Q Experience on a Windows 7 operating system and using the Google Chorme browser. I can completely assemble my circuit, using the IBM Quantum Composer and when executing it ...
- 79
3
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1
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75
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Gate characteristics of different platforms
I would like to know if there is a place in which is summarized the gate characteristics of the different quantum computer existing (IBM,Google, others).
For instance, which kind of two qubit gate ...
- 1,962
5
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1
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891
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Why are there such different UGate and U3Gate implementations in the Qiskit documentation?
The documentation for the new version Qiskit 0.20.0 states that:
UGate is "Implemented using two X90 pulses on IBM Quantum systems:
$U(θ,ϕ,λ)=RZ(ϕ−π/2)RX(π/2)RZ(π−θ)RX(π/2)RZ(λ−π/2)$"
...
- 306
1
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1
answer
71
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Dose Quantum threshold theorem apply to IBM Quantum Experience
According to Quantum threshold theorem, error rate can be arbitrarily low. But when I use IBM Quantum Experience to measure a simple $|+\rangle$, it gives result of $|1\rangle$ with probability of 52....
- 113
4
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146
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Form and effect of the intrinsic Hamiltonian on the IBM machines
I want to understand the form of the intrinsic Hamiltonian of the IBM machines, such as ibmq_16_melbourne, and how this affects the data I get out when waiting ...
5
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1
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369
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Do all physical architectures for quantum computers use the same universal gate sets?
Now I have understood that physical implementation of quantum computer need a universal quantum gate set like Clifford+T to realize any unitary quantum gate. However, I don't know if it is all the ...
- 467
5
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2
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405
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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 ...
- 14.9k
2
votes
1
answer
77
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Is it possible to build a quantum processor with connections among all qubits?
Current quantum processors have constrained connectivity among qubits. For example Starmon-5 processor by Quantum Inspire has only one qubit connected to others, effectively it looks like a star. The ...
- 14.9k
6
votes
2
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963
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What are examples of quantum computing platforms availble for free (other than IBM Q)?
IBM Q is (maybe first) quantum computing platform allowing users to register for free and run algorithm on real quantum processors. There are several processors with usually 5 qubits, however, it is ...
- 14.9k
1
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0
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53
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How qubit phase is build in real hardware?
How qubit phase is build in real hardware?
On IBM Quantum, D-Wave, etc?
- 313
8
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1
answer
2k
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Physical implementation of gates on IBM Q
There is a lot of quantum gates in IBM Q Composer, however, only few are implemented physically while others can be composed of them.
When one looks at description of a quantum processor in IBM Q ...
- 14.9k
18
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1
answer
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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 ...
6
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1
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What is the state of the art on Quantum Random Access Memories? [duplicate]
I realized that Quantum Random Access Memory (qRAM) was proposed to make quantum computers more similar to classical one. Currently quantum computers have very constrained memory, given only quantum ...
- 14.9k
8
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2
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1k
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Changing one qubit causes changes in another independent qubit on ibmqx2 in IBM Q Experience
When I run this program on ibmqx2 (the backend matters) in IBM Q Experience, the results are interesting. Essentially, the program measures the error rate on $|q_0\rangle$ after fiddling with $|q_1\...
- 137
3
votes
1
answer
117
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Writing twice to same classical register -> 1 for some backends in IBM Q Experience
On some backends, measuring the same expected value twice to the same classical register always leaves that classical register in the "1" state. I don't know if these results will hold over time, but ...
- 137
6
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1
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221
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Reversal of time arrow on IBM Q
It is well known that a quantum computer is reversible. This means that it is possible to derive an input quantum state $|\psi_0\rangle$ from an output $|\psi_1\rangle$ of an algorithm described by a ...
- 14.9k
2
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2
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159
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Simple program produces consistently skewed results in IBM Q Experience
I'm running this program (essentially a two bit random number generator) on ibmqx2 in IBM Q Experience. The backend matters. Other machines give unexpected results, but the graph looks different for ...
- 137
7
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1
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2k
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Why use U2 and U1 gate in IBM quantum computers?
I was wondering why IBM's computer were using U1 and U2 gates as part of there basis gates since as I understood, they are particular cases of the U3 gate. Why not just use U3 gate instead ?
Thanks ...
- 345
2
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1
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119
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How many physical qubits are used when I run a program on a IBM Q computer?
How do I find out how many physical-qubits I'm using when I run my program in an IBM Q backend quantum computing system?
