A classical computer has a memory made up of bits, where each bit represents either a one or a zero and its implemented by two-state transistor logic.
However, a quantum computer maintains a sequence of qubits. A single qubit can represent a one, a zero, or any quantum superposition of those two qubit states; a pair of qubits can be in any quantum superposition of 4 states, and three qubits in any superposition of 8 states. In general, a quantum computer with $n$ qubits can be in an arbitrary superposition of up to $2^n$ different states simultaneously (this compares to a normal computer that can only be in one of these $2^n$ states at any one time).
How could memory be organized(implemented) in quantum computers?
How are these complex (superposition) states saved?