qiskit-community / ibm-quantum-challenge-2024

For IBM Quantum Challenge 2024 (5-14 June 2024)
https://challenges.quantum.ibm.com/2024
Apache License 2.0
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Lab 1 #27

Open Jer-lin opened 4 weeks ago

Jer-lin commented 4 weeks ago

why Can't i build a bell state circuit with single z and x and cnot gate but it's possible with H gate... (Lab1) any help is greatly appreciated

dr-kinder commented 3 weeks ago

With single X and Z gates, you cannot put either state into a superposition of |0> and |1>. Z multiplies each state by ±1 and X flips each state. You need H to get a superposition: H|0> = |0> + |1>. After this, the CNOT gate can entangle two qbits. With additional Z and X gates, you can create any of the 4 bell states.