This document provides an introduction to quantum computing, including: - The first quantum computer, Orion-2007, was based on superconducting electronics and benefited from lower energy consumption and higher performance. - Quantum computers can solve certain problems exponentially faster than classical computers by taking advantage of quantum parallelism and superposition states to evaluate functions for multiple input values simultaneously. - Key challenges for quantum computing include preventing decoherence, avoiding the Zeno effect, and managing quantum entanglement between qubits.

1. Quantum Computing

2. INTRODUCTION
• Energy consumption
• Speed
• Qubit
• 0&1
• Superposition state

3. The world's first quantum computer?
• Orion-2007
• based on superconducting electronics
• Superconductors can be used to build large structures that behave
according to the rules of quantum mechanics
• Less energy consumption
• High performance
• E.g. search for phone number in world phonebook

5. 2 Theory of QC
• 2.1 The power of quantum computers
• Clock speed
• Number of steps to calculate a problem.
• Comparison between QC & CC
• Complexity theory
• Time
• Space
• Energy
• Factoring number in to its prime numbers
• O(e^n1/3) for normal algorithms.
• O(n3) for quantum algorithms.
• Searching unsorted database, Communication tasks etc.

6. • 2.2 Quantum parallelism
• Reversibility
• Heat generation
• superposition states
• 0 & 1
• 0+1 written as a|0〉 + b|1〉,
• where a and b are complex numbers satisfying |a|^2 + |b|^2 = 1.
• In some sense, this means that a qubit can be in |0〉 and |1〉 at the same time
• An “equal” superposition of |0〉 and |1〉.
• The output state is now a superposition of the two output values. In this
sense, function f is evaluated for both possible input values in one step.

7. • Two qubits with in a superposition of |0〉 and |1〉
• c0|00〉 + c1|01〉 + c2|10〉 + c3|11〉
• A 2-qubit logic gate g will transform this state to
• c0|g(00)〉 + c1|g(01)〉 + c2|g(10)〉 + c3|g(11)〉 (4)
• So in a sense g has been evaluated for four input values in parallel.
For every extra qubit involved in the computation, the number of
parallel function evaluations doubles. This exponential parallelism
became known as quantum parallelism.

8. 2.4 Requirements and challenges
• Requirements
• a system of qubits.
• the qubits must be individually addressable and must interact with each other
• it must be possible to initialize them to a known state because the result of a
computation generally depends on its input state.
• we must be able to extract a computation result from the qubits by some
measurement.

9. • Challenges
• Decoherence: This property states that if a coherent state (state with
superposition) interacts with the environment, it will fall into a classical
physics state without superposition
• Zeno effect: States that an unstable particle, if constantly observed, will never
decay into a superpositioned state
• Entanglement: two or more particles can be linked, and if linked, you can
change properties of one particle changing the linked one.

10. 3. FUTURE OF QUANTUM COMPUTING
• Artificial Intelligence
• High performance will allow us in development of complex compression
algorithms
• voice and image recognition
• molecular simulations
• true randomness
• Molecular simulations are important for developing simulation applications
for chemistry and biology
• Cryptography
• Peter Shor’s Algorithm

11. THANK YOU