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Figure 3. Ratio of the minimum energy require for the computation.
In this figure, the horizontal axis is for the wavelength of tunneling photons and the
vertical axis is for the ratio of their energy required for the computation.
If the wavelength of the tunneling photon is in a far infrared region
5 nm
, the
energy cost of computation for the computer, which consists of QTP gates, reaches to
times smaller than that of conventional computer systems.
In recent years, many studies on the quantum computation were conducted and it was
recognized that the computational speed by quantum computing was much higher than that of
conventional silicon processors. But the energy cost due to the uncertainty principle which
prevents speeding-up of the quantum computation was not considered.
From the theoretical analysis of the energy limit of the quantum computer system which
utilizes tunneling photons, it can be shown that energy loss of computation by utilizing
superluminal tunneling photons is much lower than that of conventional silicon processors.
Moreover this superluminal effect can eventually speed up computers significantly because it
can compensate interconnect delays inside logic gates which can never be fully eliminated
from any real electronic components and bringing overall transmission rate closer to the
ultimate speed limit [Chiao et al., 2001], which actually boost the speed of a signal traveling
on an electromagnetic wave for achieving high performance computers.
Another problem for conducting quantum computation is decoherence of quantum states.
The qubit calculations of the quantum computer are performed while the quantum wave
function is in a state of superposition between states, which is what allows it to perform the
calculations using both 0 and 1 states simultaneously.
But this coherent state is very fragile and difficult to maintain. By the slightest interaction
with the external world would cause the system to decohere. This is the problem of
decoherence which is a stumbling block for quantum computation. Therefore the computer
has to maintain the coherent state for making calculations.
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