The double-slit experiment is a fundamental experiment in quantum mechanics that demonstrates the wave-particle duality of particles. It has been performed with various particles, ranging from electrons to large molecules. However, the practical limitations and challenges increase significantly as the size, mass, and complexity of the particles increase.
To date, the largest and heaviest particles for which the double-slit experiment has been successfully demonstrated are molecules consisting of a few hundred atoms. For example, experiments have been conducted using molecules like fullerenes (C60) or phthalocyanine (C32H18N8). These molecules have sizes on the order of nanometers and masses on the order of picograms.
The reason why the double-slit experiment becomes more challenging as the particle size increases is due to the increased interactions and decoherence effects with the surrounding environment. Larger particles are more prone to collisions, interactions, and decoherence, which can disrupt the interference patterns observed in the experiment.
Performing the double-slit experiment with macroscopic objects, such as everyday objects or organisms, is currently not feasible due to the significant challenges of maintaining the coherence and isolation required for observing interference patterns.
It's worth noting that advancements in experimental techniques and technologies are continuously pushing the boundaries of the double-slit experiment. Researchers are exploring ways to extend the size and complexity of particles that can be successfully used in the experiment, but there are still practical limitations to consider.