Usually, it is not easy to de?ne the main dates of creation of a new science - the birth date, when the ?rst distinct idea was generated, and the - turity date, when the science manifested itself as a separate and consistent discipline. For particle astrophysics, the science that has developed very - tensively over the last two decades, the birth is most likely to be dated to the beginning of the 1930s. Just then, after the discovery of a neutron by J. Chadwick in 1932, the concept of a neutron star was proposed by L.D. L- dau, and independently by W. Baade and F. Zwicky. The maturation of...

The study of semiconductor heterostructures started more than forty years ago. In the 1980s this area of research moved to the forefront of semiconduc tor physics, largely due to progress in growth technologies which are now capable of producing ultrathin layers (up to a few monolayers) of different semiconductor materials. The availability of structures with nearly ideal, well-controlled properties has made semiconductor heterostructures a test ing ground for solid-state physics. These structures have had a profound impact on basic research in semiconductor physics by opening new possibil...