Practical MOSFET Quantum Computer with Millions of Qubits

We propose a practical quantum computer (QC) operating at room temperature and ambient pressure, distinct from existing approaches. The QC is based on MOSFETs that act as qubits, forming superpositions of ∣0⟩ and ∣1⟩ and readily composing Bell states through transistor-based circuits. These circuits implement quantum gates such as C-NOT, Z, Toffoli, and arbitrary rotations. A unique feature of the MOSFET qubit is its non-destructive measurement property, which allows intermediate results to be stored in memory. The QC employs a massively parallel architecture in which each state of multi-qubit superpositions is assigned an independent quantum processing unit (QPU), enabling accelerated computation; this is illustrated through the factorization of N = 15 using Shor's algorithm. With advanced semiconductor processes such as Samsung's 2-nm or Intel's cutting-edge platforms, scalable chips with more than one million qubits could be realized within 3 years. Beyond quantum algorithms, the QPU-rich design can be applied to artificial intelligence, providing hybrid quantum–classical capabilities.