Qubits, or quantum bits, are the fundamental units of information in a quantum computer. Unlike classical bits, which can store either a 0 or a 1, qubits can exist in a superposition of both 0 and 1 states simultaneously. This property allows quantum computers to perform certain computations much faster than classical computers for specific problems.
However, qubits are fragile and can be easily disturbed by their surrounding environment, leading to errors in the computation. This phenomenon is called quantum decoherence. Maintaining the coherence of qubits is one of the biggest challenges in building practical quantum computers.
Additionally, qubits are highly sensitive to noise and interference from factors such as temperature fluctuations and electromagnetic radiation. As a result, quantum computers require extremely low temperatures and carefully controlled environments to minimize these disturbances and preserve the integrity of the qubits.
Another factor is the need for quantum error correction. Since qubits are prone to errors, quantum error correction techniques are necessary to detect and correct these errors. However, implementing error correction introduces additional overhead, requiring a larger number of qubits to perform reliable computations.
Overall, while qubits offer immense potential for performing complex computations, their delicate nature and susceptibility to errors present significant challenges in building and scaling practical quantum computers. Researchers and engineers are actively working on addressing these challenges to advance the field of quantum computing.