2025 Nobel Prize in Physics for Quantum Tunnelling
Why focus: GS3 Sci-Tech — core applied physics. Expect Assertion-Reason MCQs on macroscopic quantum tunnelling mechanics and energy quantisation.
In News
What Happened
Why It Matters
Background
History & Context
What Changed
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Scope of Quantum Tunnelling: BEFORE the experiments, tunnelling was only experimentally proven and widely believed to apply to single atomic or subatomic particles. NOW, the laureates proved that quantum tunnelling can occur collectively in a macroscopic system (an electrical circuit).
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Concept of Energy Quantisation: BEFORE, discrete, quantised energy levels were considered an exclusive property of single atoms or molecules. NOW, macroscopic electrical circuits were proven to possess discrete energy states, effectively functioning as controllable 'artificial atoms'.
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Understanding of Superconductors: BEFORE, macroscopic superconducting circuits were largely treated using classical electrical engineering and thermodynamic models. NOW, it is proven that they are governed by the rules of circuit quantum electrodynamics (circuit QED) and can exhibit probabilistic wave-like behaviour.
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Quantum Computing Hardware: BEFORE, theoretical proposals for quantum computers lacked a viable, physical, and scalable hardware platform. NOW, their discovery established superconducting circuits (using Josephson junctions) as the leading physical architecture for modern qubits, currently utilised by tech giants like Google and IBM.
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Handling of Environmental Noise: BEFORE, thermal noise and environmental interactions were assumed to permanently destroy quantum coherence (decoherence) in any macroscopic object. NOW, the sophisticated filtering techniques developed by the trio demonstrated exactly how to eliminate noise to preserve collective macroscopic quantum states.
What Did NOT Change
Despite this monumental leap, the fundamental mathematical equations governing quantum mechanics, such as the Schrodinger equation, remained exactly the same; they were simply successfully applied to a new, collective variable (the phase difference of a Josephson junction). Furthermore, observing these macroscopic quantum effects still strictly requires extreme laboratory conditions, primarily ultra-low temperatures near absolute zero, to prevent immediate decoherence from ambient heat.
Prelims Angle
NCERT Connection
Common Misconceptions
✗ Quantum tunnelling and quantisation only occur at the microscopic scale of single atoms or subatomic particles.
✓ The 2025 Nobel laureates definitively proved that a macroscopic superconducting circuit containing billions of paired electrons can undergo quantum tunnelling and exhibit quantised energy states.
For over half a century, physics curricula taught quantum mechanics strictly as the physics of the microscopic world, because macroscopic objects usually lose their quantum properties instantly due to environmental interaction.
✗ The 2025 Nobel Prize in Physics was awarded for discovering the quantum tunnelling effect.
✓ The prize was awarded specifically for discovering MACROSCOPIC quantum tunnelling in a collective electrical circuit, not the fundamental quantum tunnel effect itself, which was known for decades.
Mainstream media headlines often shorten complex scientific discoveries to 'quantum tunnelling', omitting the crucial modifier 'macroscopic' which is the actual breakthrough.
Practice Questions
Q1
How Many CorrectConsider the following statements regarding the 2025 Nobel Prize in Physics: 1. The prize was awarded for the initial theoretical prediction of the Josephson effect in superconducting materials. 2. The laureates demonstrated that a macroscopic electrical system consisting of billions of Cooper pairs could exhibit discrete, quantised energy levels. 3. The groundbreaking experiments that led to this award were conducted using highly shielded superconducting electrical circuits in the 1980s. How many of the above statements are correct?
Q2
Match the FollowingMatch List I (Concept/Component related to the 2025 Nobel Prize) with List II (Its description/role): List I: A. Cooper pairs B. Josephson junction C. Circuit QED D. Thermal noise List II: 1. A component comprising two superconductors separated by a thin insulator, crucial for the tunnelling experiment. 2. The environmental interference that the laureates had to rigorously filter out to preserve quantum coherence. 3. The collective charge carriers in the superconductor that behaved in unison as a single quantum entity. 4. The field of study born from this discovery, essential for modern superconducting quantum computers. Select the correct answer using the code given below:
Q3
Assertion & ReasonAssertion (A): The discoveries by John Clarke, Michel H. Devoret, and John M. Martinis established the experimental foundation for modern superconducting quantum computers. Reason (R): They successfully proved that an engineered, macroscopic electrical circuit can exhibit quantised energy states and tunnel through classically forbidden barriers without losing quantum coherence. Select the correct answer: