We present CoordAuth, a gaze-based two-factor authentication technique in VR utilizing implicit head-eye motion features to offer a more secure and natural alternative to traditional pattern-based authentication. Users authenticate by performing gestures across 3×3 grid points using their eyes. We first optimized CoordAuth’s UI by evaluating participants’ input performance and experiences across different grid sizes. Then we extracted the head-eye coordination features during pattern entering to construct CoordAuth’s authentication algorithm, which ensembles Random Forest classifiers across saccade and fixations segments. CoordAuth demonstrated strong security with a 1.6% FAR and 1.5% FRR across 24 registered users in the password collision scenarios. A subsequent study demonstrated that CoordAuth achieved an 0.6% Attack Success Rate (ASR) against shoulder-surfing attack from a 1-meter distance. Usability evaluations in standing, sitting, and moving postures showed that CoordAuth achieved significantly faster authentication speed and lower rejection rate than laser and touch-based baselines. Meanwhile, it was the most preferred by the participants in terms of social acceptance and physical effort.

While generative artificial intelligence (GenAI) is finding increased adoption in workplaces, current tools are primarily designed for individual use. Prior work established the potential for these tools to enhance personal creativity and productivity towards shared goals; however, we don't know yet how to best take into account the nuances of group work and team dynamics when deploying GenAI in work settings. In this paper, we investigate the potential of collaborative GenAI agents to augment teamwork in synchronous group settings through an exploratory study that engaged 25 professionals across 6 teams in speculative design workshops and individual follow-up interviews. Our workshops included a mixed reality provotype to simulate embodied collaborative GenAI agents capable of actively participating in group discussions. Our findings suggest that, if designed well, collaborative GenAI agents offer valuable opportunities to enhance team problem-solving by challenging groupthink, bridging communication gaps, and reducing social friction. However, teams' willingness to integrate GenAI agents depended on its perceived fit across a number of individual, team, and organizational factors. We outline the key design tensions around agent representation, social prominence, and engagement and highlight the opportunities spatial and immersive technologies could offer to modulate GenAI influence on team outcomes and strike a balance between augmentation and agency.