Questions tagged [ibm]
For questions about IBM's quantum computing processors and devices. For their cloud-computing service use the [ibm-q-experience] tag instead.
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How can I find the documented T1 time of a retired IBM system?
I need to find the published mean T1 time for the 'ibm_oslo' system that I used in an experiment a while back. Unfortunately, that system has now been retired and there's seemingly no way for me to ...
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Phase estimation of the Pauli-Y matrix
I'm trying to use the phase estimation algorithm to extract the eigen value for both eigen vectors of the Pauli-Y matrix using the ibm quantum experiance.
So far I have this for the possitive state |+&...
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How does Qiskit CircuitSampler class calculate expectation values of operators?
I have been using Qiskit CircuitSampler class to calculate the expectation values of operators as described here. Now it turns ...
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Execute using circuits on IBM hardware using visual studio code
I have wrote some code using Qiskit in Jupyter notebook using Microsoft Visual Studio Code. Is there any way to run directly on an IBM quantum computer through Visual Studio?
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Sycamore 2 versus Osprey
Google recently hit key milestone by reducing errors: https://www.nature.com/articles/d41586-023-00536-w
I would like to know why Google's QPU had way fewer qubits than IBM's Osprey and if IBM also ...
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How do I change the x and y axis on the results histogram for a ibmq_qasm.simulation resulting histogram?
Im following a textbook and when they ran the same circuit with the ibmq_qasm_simulator, their results histogram had computational basis state on the x axis and probability on the y axis, however my ...
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Circuit containing only Hadamard gate returns bad results
I am new to quantum computing. My circuit contains only one qubit, one Hadamard gate and an operation to measure the state of the qubit. So, as I understand, the qubit is in superposition state after ...
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What problems can quantum computers solve right now which classical computers cannot solve? [duplicate]
I know that an error-corrected quantum computer with unlimited amount of qubits can provide a significant speed up compared to classical computers for specific kind of problems, e.g. searching in an ...
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IBM composer deletes my circuit
When I work on the IBM quantum composer and I switch to another circuit, my first circuit is destroyed and replaced by the second one. I thought it was a display bug, but when I restart the composer, ...
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Difference between IBM simulator backends
I'm an Msc student working on a quantum information project (VQEs on 4 qubits).
Our group is looking at different IBM simulators on the IBM platform, and have noticed that performance is different for ...
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I've wrote code on an outdated version of QisKit but what to run it on a quantum computer
like mentioned in the title I've got working code on an outdated version of QisKit which I run on my own IDE. However I am wanting to run this on a real quantum computer and I can't do this as IBM ...
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problem with parametrized circuits
I used a circuit with one parametrized gate U(theta, phi, lambda), than I fixed the parameters with qc.bind_parameters and it's worked well. But the only step that don't work is the execution in a ...
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How the real IBM quantum computers apply arbitrary Rz(θ) gate rotation? [closed]
I want to ask the following questions:
(1) The basis gate set of IBM quantum computers is { Id, Rz(θ),√X, X, CNOT, reset}. Somebody said that IBM didn’t really apply Rz(θ) gate on the machine. The ...
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'RuntimeJob' object has no attribute 'queue_position'
I was trying to run a QAOA job using the below script:
...
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Can I set the gate time of ibmq_qasm_simulator or what is the default time?
Actually I want to know how the noise model add error to circuit gate.
Thank you.
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what quantum computing simulator can achieve drag-and-drop programing fuction without internet like IBM web composer?
I reallt need some kind of simulator can work like this.Quirk is similar but also require internet.can anyone know how to achieve this?It is very important for some eaducational lesson to students.
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Time Complexity (Big O Notation)
What is the time complexity of the two error-mitigation methods that are implemented in qiskit.ignis.
1- pseudo inverse.
2- least squares.
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Extracting results from a job when it is in a json form
I have downloaded a job from the COMPOSER JOBS but I get a folder containing three files.
632867a95ccea778be9446fb-info.json
632867a95ccea778be9446fb-input.json
632867a95ccea778be9446fb-output.json
...
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Retrieving jobs of an expired access device
I had private access to a quantum computer, but the access is expired. So Can I access to my jobs done on it ?
The '''backend.retrieve_job('')''' can't work because I cant load the backend (no access)...
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How to stretch duration of standard gates of an IBM Backend?
I want to stretch the duration of standard gates of an IBM backend to amplify noise (as proposed in one of the earliest implementations of zero noise extrapolation (ZNE) (https://arxiv.org/abs/1805....
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What can I use instead of mct (multi-controlled Toffoli)? (Grover's algorithm)
I implemented the general diffuser (for arbitrary qubits) in Grover's algorithm in terms of an Multi-controlled Toffoli (MCT) gate (it flips target when all controlled gates are 1). However, this gate ...
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how to fix error 'QiskitBackendNotFoundError' [closed]
This is my code:
from qiskit import IBMQ
IBMQ.load_account()
provider = IBMQ.get_provider('ibm-q')
qcomp = provider.get_backend('ibmq_16_melbourne')
...
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How does it work QasmSimulator with the option "density matrix"?
I am making some simulations on IBM Quantum Lab and as backend I tried to use QasmSimulator(method = "density_matrix") in order to simulate noise. I wanted to know how this method works in ...
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Interpreting VQE and QAOA based solutions in portfolio optimization
I am going through portfolio optimization using Qiskit. It really looks interesting. The module has both VQE and QAOA algorithms for optimizing the portfolios.
In the VQE based solution the ...
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Iterative quantum phase estimation - real device
I'm trying to implement the iterative quantum phase estimation on a real (IBM) quantum computer. I'm using the code below. When I run this code on a simulator the results are the expected ones, but ...
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Why is there a frequency difference when performing ramsey experiment with setting neighbor qubits to different state?
For transmon qubits, there is an always-on zz interaction between coupled qubits, thus introducing static zz crosstalk. The figures are from this paper.
I know zz crosstalk can change the frequency of ...
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Quantum State Tomography Implementation in IBMQ
I am working to understand quantum state tomography, specifically using the algorithm presented in PRL 108, 070502. This paper is referenced in IBMQ implementations of QST, both in old deprecated ...
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How can I get IBM's API token?
I need an API token to use IBM's real hardware(greater than 5 qubits) in Qiskit, where can I find the price?
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What use cases are there for 127 qubit QPUs?
IBM have recently announced their 127 qubit Eagle processor. Other approaches, such as Rydberg arrays, have now 256 qubits, as for example in QuEra's QPU QPU.
While these are without a doubt ...
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Is the error rate of IBMQ devices full-scale (% FS) or on percentage of reading (% RD)?
The error rates that I found on the calibration files are given in percentage, but I couldn't find whether it is calculated on full-scale (% FS) or on percentage of reading (% RD). If I do $20000$ ...
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Can the ancilla for Qiskit's mcx with mode="recursion" be dirty?
I think their implementation is close to the one from here which does use a dirty ancilla, but I just want to make sure
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Strange behaviour of IdentityGate IGate in IBM Q Composer
Can anyone explain the strange impact of the IGate in the enclosed quantum teleportation setup in view of the computational basis states? Any help is welcome!
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Difference between Aer.get_backend('aer_simulator') and AerSimulator()
In Qiskit, there are several ways to choose simulator: one is
from qiskit import Aer
backend = Aer.get_backend('aer_simulator')
result = backend.run(circ).result()
...
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How much information is stored in entangled states (IBM report Quantum Decade)?
In its report Quantum Decade, IBM claims that we need 512 classical bits to represent two-qubits entangled state (see graphic on pg. 2 in the report). This seems a little bit odd to me.
Lets have a ...
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Why can two target superconducting processors with the same layout get different transpilation results?
I compile and run the same small Grover circuit for 6 different processors.
ibmq_santago, manila and bogota all have a linear layout, while quito, belem and lima have qubits arranged in a T-shape.
I ...
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This is a question about IBM quantum circuit used to generate the quantum cheque state
I'm learning about quantum cheque. And I read "Experimental realization of quantum cheque using a five-qubit quantum computer" which is written by Bikash K. Behera ,Anindita Banerjee and ...
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Why probabilites are not 50-50 in this simple circuit?
I am "brand new" to IBM quantum computing. Just created an account and tried my first circuit with a Hadamard applied to $|0 \rangle$ which should lead to $(|0\rangle + | 1 \rangle)/\sqrt{2}$...
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What are the runtimes of the different modes of qiskit's mcx?
Qiskit's mcx has four different modes:
'noancilla': Requires 0 ancilla qubits.
'recursion': Requires 1 ancilla qubit if more than 4 controls are used, otherwise 0.
'v-chain': Requires 2 less ancillas ...
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Good resources for seeing qubit control pulse shapes (Transmon qubits)
I'm looking for resources which can show the pulse shapes for various single-qubit and two-qubit gates.
More specifically, is there any resource which can show me calibrated pulse shapes so that I can ...
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When will Qiskit Runtime be available to all users?
IBM's Qiskit Runtime was recently made available to a select group of users. Have they announced when it will be available to all users or when they might open it back up to a second round of new ...
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Qiskit - lesson 3 - with Abe
Coding for Qiskit
I watched this video:
https://www.youtube.com/watch?v=RrUTwq5jKM4
Using Mac OS Big Sur
Using Jupyter 2.0.8
Using Python 3.8
The below code did not work and therefore installed ...
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How do I send a quantum circuit to IBM for execution?
I have, let's say, the following quantum circuit:
The QASM code of this quantum scheme has the following form:
...
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IBM Quantum API for Java Developers
As far as I know, IBM Quantum provides two types of APIs: one for Qiskit, and the other for third-party uses (API for developers).
In this question, there are several arguments about using the API for ...
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CNOT error rate of 1 in IBM backends
I have noticed that some CNOT gates (for instance, between qubits 1 and 2 in ibmq_casablanca) display an error rate of 1 while typical error rates are of course ...
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IBM quantum computer giving the wrong result?
This is the first time I am using the IBM quantum computer. I tried to run a circuit (see below the first picture) but the results I got don't match the theoretical results shown (see below the second ...
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Who is responsible for implementing quantum error correction?
There are various options for error correction. For example, the Shore code or a whole class of surface codes.
But I don't really understand at what level they should be implemented.
For example, I ...
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Does a quantum computer exist today? [closed]
I agree that this may not be an easy question to answer.
But lately, I increasingly come across the fact that many news materials and research papers in the field of quantum technologies say that at ...
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Is there any way to obtain the number of qubits of a given backend in Qiskit?
I'm testing out a program in different IBMQ mock backends, and I want the program to use the maximum number of qubits in each case. Is there any function/method to extract the number of qubits of a ...
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Can I use Quantum lab during IBM Quantum certification exam? [closed]
Hello I am about to take the IBM Quantum Qiskit dev exam. I don't know if I can use the quantum lab (Qiskit) during the exam. Does anyone know?
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