Dynamics of spin mixtures in a Bose-Einstein condensate with dipolar interactions

• Grant number: 25/19167-0
• Support Opportunities: Scholarships abroad - Research
• Start date: February 01, 2026
• End date: April 30, 2026
• Field of knowledge: Physical Sciences and Mathematics - Physics - Atomic and Molecular Physics
• Principal Investigator: Patrícia Christina Marques Castilho
• Grantee: Patrícia Christina Marques Castilho
• Host Investigator: Raphael Lopes
• Host Institution: Instituto de Física de São Carlos (IFSC). Universidade de São Paulo (USP). São Carlos , SP, Brazil
• Institution abroad: Collège de France, France

Abstract

Ultracold dipolar gases are very exciting systems where the interplay between contact and dipole-dipole interactions led to the observation of phenomena not possible in standard alkaline atom systems. Self-bounded quantum droplets [1-3] and the roton instability [4] have been have been extensively explored in single-species dipolar systems as well as its supersolid state [5-7], where crystalline order coexist with a phase-coherent superfluid behavior. All these findings motivated the search for other unusual states of matter extending the interest to dipolar quantum mixtures realized with different magnetic atoms (such as Er-Dy [8, 9]) or by combining two states of the same atomic species [10]. In such cases, exotic quantum droplets in both miscible or immiscible systems are possible [11] and are not restricted to a well-defined ratio between the components (as for the case of droplets in standard alkaline mixtures [12,13]) and droplets-like density modulations can occur even when the single component system would not show any modulation, induced only by the doping with the secondary species [14]. In this project, we propose to explore for the first time the onset of droplet-like density modulations in a dipolar mixture composed of the two lowest ground-states of 162Dy [10]. Characterizing the phase diagram of the modulated mixture system and obtaining its dispersion relation will allow to relate the state of the system with a new kind of supersolid where the interplay between density and spin degrees of freedom may give rise to exciting new phenomena.