The authors propose and analyze a theoretical experimental setup for detecting Majorana fermions in semiconductor-superconductor (S-S) heterostructures. The system consists of a one-dimensional (1D) semiconductor wire with strong spin-orbit Rashba interaction embedded in a superconducting quantum interference device (SQUID). They show that the energy spectra of Andreev bound states at the junction differ qualitatively between topologically trivial and nontrivial phases, with an even and odd number of crossings at zero energy, respectively. By measuring the supercurrent through the junction, the authors demonstrate that this difference can be used to discern topologically distinct phases and observe a topological phase transition by changing the in-plane magnetic field or gate voltage. This transition would directly confirm the existence of Majorana particles, which are exotic fermions that are their own antiparticles and are sought for fault-tolerant topological quantum computation. The proposed setup is simple and does not require specialized materials, making it experimentally feasible.The authors propose and analyze a theoretical experimental setup for detecting Majorana fermions in semiconductor-superconductor (S-S) heterostructures. The system consists of a one-dimensional (1D) semiconductor wire with strong spin-orbit Rashba interaction embedded in a superconducting quantum interference device (SQUID). They show that the energy spectra of Andreev bound states at the junction differ qualitatively between topologically trivial and nontrivial phases, with an even and odd number of crossings at zero energy, respectively. By measuring the supercurrent through the junction, the authors demonstrate that this difference can be used to discern topologically distinct phases and observe a topological phase transition by changing the in-plane magnetic field or gate voltage. This transition would directly confirm the existence of Majorana particles, which are exotic fermions that are their own antiparticles and are sought for fault-tolerant topological quantum computation. The proposed setup is simple and does not require specialized materials, making it experimentally feasible.