Day13 of #Quantum30 Challenge
Hello, fellow learners! On the Day 13 of #Quantum30 Challenge, I learned about Quantum Annealing, What is quantum annealing, difference in quantum annealers and universal gate based quantum computers, How quantum annealing processors work, and so on. Let’s go through the learning log.
The first resource is “Quantum Annealer vs Universal Gate Based Quantum Computers | Is D-Wave a Real Quantum Computer?” from the YouTube channel Anastasia Marchenkova. Let’s go!
Quantum Annealers:
Quantum annealers are specialized quantum computers designed to tackle optimization problems efficiently. These problems involve finding the best solution from a vast number of possibilities. Imagine searching for the shortest route in a complex network or determining the optimal arrangement of components in a system.
The annealing process, from which these computers derive their name, is inspired by the concept of annealing in metallurgy. In metallurgy, annealing involves heating a material and then slowly cooling it to alter its properties. In the context of quantum annealing, quantum fluctuations are used to explore and settle into the lowest energy state of a system, which corresponds to the optimal solution for an optimization problem.
Universal Gate Quantum Computers:
Universal gate-based quantum computers, in contrast, offer a more versatile approach. They can execute a wide range of algorithms by manipulating qubits using various quantum gates. These gates operate on individual qubits or pairs of qubits, enabling the creation of complex quantum circuits.
The concept of reversibility is fundamental to quantum gates. Unlike classical logic gates, which can lead to information loss, quantum gates preserve information due to the reversible nature of quantum operations. This is crucial for maintaining the delicate states of superposition and entanglement that give quantum computers their computational power.
Divincenzo Criteria and Quantum Volume:
The Divincenzo criteria provide a set of requirements that a physical quantum system must meet to be considered a viable quantum computer. These criteria address aspects such as qubit stability, initializability, and the ability to perform quantum gates accurately. Adhering to these criteria ensures that the quantum system can support reliable quantum computations.
Quantum volume, introduced by IBM, extends the concept of assessing quantum computers beyond qubit counts. It considers multiple factors that impact a quantum computer’s performance, including qubit quality, error rates, and system connectivity. Quantum volume offers a more comprehensive picture of a quantum computer’s capabilities, highlighting its practical utility beyond mere qubit quantity.
Limitations and Progress:
While quantum computing holds immense promise, it is important to recognize its limitations. Quantum computers excel at specific types of problems, particularly those involving complex optimization and simulation tasks. However, they are not universally superior to classical computers for all types of computation.
The field of quantum computing is rapidly evolving, with significant progress being made in qubit quality, error correction techniques, and algorithm development. Quantum error correction, in particular, is a crucial area of research as it seeks to mitigate the effects of noise and errors that naturally occur in quantum systems.
The second resource is “How The Quantum Annealing Process Works” from the YouTube channel of D-Wave. The video revolves around how the quantum annealing processor works. Let’s go through the summary of the video
Introduction:
The video aims to explain how quantum annealing works. The focus is on understanding the process behind the quantum annealing processor.
Single Qubit and Superposition:
A qubit can exist in states 0 or 1, encoded using circulating currents and magnetic fields. Due to its quantum nature, a qubit can also be in a superposition of 0 and 1 simultaneously. Quantum annealing involves transitioning from superposition to either 0 or 1 states. The energy diagram visualizes this process, where a double well potential represents the qubit's states.
Controlling Probabilities:
An external magnetic field called bias is applied to control the probabilities of a qubit ending up in 0 or 1 states. This bias tilts the energy diagram, increasing the likelihood of one state over the other.
Couplings and Entanglement:
Couplers link qubits together, allowing them to influence each other's states. Couplings can make qubits prefer the same state or opposite states. This introduces the concept of entanglement, where qubits are treated as a combined system with multiple possible states.
Programming with Biases and Couplings:
By applying biases and setting couplings, users program the quantum computer. This defines an energy landscape, determining the system's behavior. The quantum annealer aims to find the minimum energy state of this landscape.
Complexity and Exponential States:
The complexity of the system increases exponentially with the number of qubits. Adding a qubit doubles the number of possible states, resulting in a substantial increase in complexity.
Summary:
Quantum annealing starts with qubits in superposition states. Through the annealing process, qubits become entangled as couplings and biases are introduced. The probabilities of qubits ending up in 0 or 1 states are controlled. Eventually, after around 20 microseconds, qubits settle into 0 or 1 states, representing the minimum energy solution or a close approximation.
Thank you, readers! QuantumComputingIndia #Quantum30
