He studied Physics at the University of Kiel and the Technische Universität Darmstadt, where he received his doctoral degree with a thesis entitled "Design, construction and testing of a corrected electron energy loss spectrometer with large dispersion and a large acceptance angle" (in German: "Entwurf, Bau und Erprobung eines korrigierten Elektronen-Energieverlust-Spektrometers mit grosser Dispersion und grossem Akzeptanzwinkel"). In 1989 he became Group Leader within the Physical Instrumentation Program at the European Molecular Biology Laboratory (EMBL) where he had already performed some experiments during his doctoral studies.
He is honorary professor at the Karlsruhe Institute of Technology (KIT); co-founder, senior advisor and former president of Corrected Electron Optical Systems GmbH (CEOS), a German company that manufactures correction components for electron microscopes.
He won the 2011 Wolf Prize in Physics, along with Harald Rose and Knut Urban, for his contributions to electron microscopy, specifically for the development of a device to correct electron-optical aberration using magnetic multipole lenses. Their work allowed electron microscopes to achieve a resolution of about 50 pm, comparable to the radius of the smallest atom. The three started working together in 1992. Haider built the first prototype and he is the founder (with Joachim Zach in 1996) of the German company Corrected Electron Optical Systems GmbH (CEOS), which manufactures and sells their invention.
In 2008 he became honorary professor at the Karlsruhe Institute of Technology (KIT).
Haider also received the 2013 BBVA Foundation Frontiers of Knowledge Award in Basic Sciences, along with Harald Rose and Knut Urban, for greatly enhancing the resolving power of electron microscopy by developing aberration-corrected electron optics, a breakthrough enabling subatomic precision.